The Mesh of Civilizations in Cyberspace

“The great divisions among humankind and the dominating source of conflict will be cultural. Nation states will remain the most powerful actors in world affairs, but the principal conflicts of global politics will occur between nations and groups of different civilizations. The clash of civilizations will dominate global politics.”

—Samuel P. Huntington (1972-2008) “The Clash of Civilizations

In 1993, the Harvard political scientist Samuel Huntington published his now infamous paper The Clash of Civilizations in the journal Foreign Affairs. Huntington hypothesized that conflicts in the post-Cold War era would occur between civilizations or cultures and not between ideologies. He divided the world into eight key civilizations which reflected common cultural and religious heritages: Western, Confucian (also referred to as “Sinic”), Japanese, Islamic, Hindu, Slavic-Orthodox, Latin-American and African. In his subsequent book “The Clash of Civilizations and the Remaking of the World Order“, which presented a more detailed account of his ideas and how these divisions would fuel future conflicts, Huntington also included the Buddhist civilization as an additional entity. Huntington’s idea of grouping the world in civilizational blocs has been heavily criticized for being overly simplistic and ignoring the diversity that exists within each “civilization”. For example, the countries of Western Europe, the United States, Canada and Australia were all grouped together under “Western Civilization” whereas Turkey, Iran, Pakistan, Bangladesh and the Gulf states were all grouped as “Islamic Civilization” despite the fact that the member countries within these civilizations exhibited profound differences in terms of their cultures, languages, social structures and political systems. On the other hand, China’s emergence as a world power that will likely challenge the economic dominance of Western Europe and the United States, lends credence to a looming economic and political clash between the “Western” and “Confucian” civilizations. The Afghanistan war and the Iraq war between military coalitions from the “Western Civilization” and nations ascribed to the “Islamic Civilization” both occurred long after Huntington’s predictions were made and are used by some as examples of the hypothesized clash of civilizations.

Globalized world

It is difficult to assess the validity of Huntington’s ideas because they refer to abstract notions of cultural and civilizational identities of nations and societies without providing any clear evidence on the individual level. Do political and economic treaties between the governments of countries – such as the European Union – mean that individuals in these countries share a common cultural identity?

Also, the concept of civilizational blocs was developed before the dramatic increase in the usage of the internet and social media which now facilitate unprecedented opportunities for individuals belonging to distinct “civilizations” to interact with each other. One could therefore surmise that civilizational blocs might have become relics of the past in a new culture of global connectivity. A team of researchers from Stanford University, Cornell University and Yahoo recently decided to evaluate the “connectedness” of the hypothesized Huntington civilizations in cyberspace and published their results in the article “The Mesh of Civilizations in the Global Network of Digital Communication“.

The researchers examined Twitter users and the exchange of emails between Yahoo-Mail users in 90 countries with a minimum population of five million. In total, they analyzed “hundreds of millions of anonymized email and Twitter communications among tens of millions of worldwide users to map global patterns of transnational interpersonal communication”. Twitter data is public and freely available for researchers to analyze whereas emails had to be de-identified for the analysis. The researchers did not have any access to the content of the emails, they only analyzed whether users any given country were emailing users in other countries. The researchers focused on bi-directional ties. This means that ties between Twitter user A and B were only counted as a “bi-directional” tie or link if A followed B and B followed A on Twitter. Similarly, for the analysis of emails analysis, the researchers only considered email ties in which user X emailed user Y, and there was at least one email showing that user Y had also emailed user X. This requirement for bi-directionality was necessary to exclude spam tweets or emails in which one user may send out large numbers of messages to thousands of users without there being any true “tie” or “link” between the users that would suggest an active dialogue or communication.

Countries are clustered based on the difference between observed and expected density of social ties in 90 countries with population above 5 million, based on interpersonal email and Twitter communication.
Credit: State et al, PloS ONE 2015Countries are clustered based on the difference between observed and expected density of social ties in 90 countries with population above 5 million, based on interpersonal email and Twitter communication.

The researchers then created a cluster graph which is shown in the accompanying figure. Each circle represents a country and the 1000 strongest ties between countries are shown. The closer a circle is to another circle, the more email and Twitter links exist between individuals residing in the two countries. For the mathematical analysis to be unbiased, the researchers did not assign any countries to “civilizations” but they did observe key clusters of countries emerge which were very close to each other in the graph. They then colored in the circles with colors to reflect the civilization category as defined by Huntington and also colored ties within a civilization as the same color whereas ties between countries of two distinct civilization categories were kept in gray.

At first glance, these data may appear as a strong validation of the Huntington hypothesis because the circles of any given color (i.e. a Huntington civilization category) are overall far closer to each other on average that circles of a different color. For example, countries belonging to the “Latin American Civilization” (pink) countries strongly cluster together and some countries such as Chile (CL) and Peru (PE) have nearly exclusive intra-civilizational ties (pink). Some of the “Slavic-Orthodox Civilization” (brown) show strong intra-civilizational ties but Greece (GR), Bulgaria (BG) and Romania (RO) are much closer to Western European countries than other Slavic-Orthodox countries, likely because these three countries are part of the European Union and have shared a significant cultural heritage with what Huntington considers the “Western Civilization”. “Islamic Civilization” (green) countries also cluster together but they are far more spread out. Pakistan (PK) and Bangladesh (BD) are far closer to each other and to India (IN), which belongs to the “Hindu Civilization” (purple) than to Tunisia (TN) and Yemen (YE) which Huntington also assigned to an ‘Islamic Civilization”.

One obvious explanation for there being increased email and Twitter exchanges between individuals belonging to the same civilization is the presence of a shared language. The researchers therefore analyzed the data by correcting for language and found that even though language did contribute to Twitter and email ties, the clustering according to civilization was present even when taking language into account. Interestingly, of the various factors that could account for the connectedness between users, it appeared that religion (as defined by the World Religion Database) was one of the major factors, consistent with Huntington’s focus on religion as a defining characteristic of a civilization. The researchers conclude that “contrary to the borderless portrayal of cyberspace, online social interactions do not appear to have erased the fault lines Huntington proposed over a decade before the emergence of social media.”  But they disagree with Huntington in that closeness of countries belonging to a civilization does not necessarily imply that it will lead to conflicts or clashes with other civilizations.

It is important to not over-interpret one study on Twitter and Email links and make inferences about broader cultural or civilizational identities just because individuals in two countries follow each other on Twitter or write each other emails. The study did not investigate cultural identities of individuals and some of the emails could have been exchanged as part of online purchases without indicating any other personal ties. However, the data presented by the researchers does reveal some fascinating new insights about digital connectivity that are not discussed in much depth by the researchers. China (CN) and Great Britain (GB) emerge as some of the most highly connected countries at the center of the connectivity map with strong global ties, including India and countries in Africa. Whether this connectivity reflects the economic growth and increasing global relevance of China or a digital footprint of the British Empire even decades after its demise would be a worthy topic of investigation. The public availability of Twitter data makes it a perfect tool to analyze the content of Twitter communications and thus define how social media is used to engage in dialogue between individuals across cultural, religious and political boundaries by analyzing culturally relevant keywords used in tweets. Analyses of Twitter data over time could test the intriguing hypothesis whether connectivity and the content of communications between users living in different countries change over time. Such a study would be even more informative in terms of linking cyberspace connectivity to cultural identities and could provide insights into the evolution of digital ties over time.



Huntington, S. P. (1993). The Clash of Civilizations. Foreign Affairs, 72(3) 22-49.

State, B., Park, P., Weber, I., & Macy, M. (2015). The mesh of civilizations in the global network of digital communication. PLoS ONE, 10(5), e0122543.


Note: An earlier version of this article was first published on the 3Quarksdaily blog.

State, B., Park, P., Weber, I., & Macy, M. (2015). The Mesh of Civilizations in the Global Network of Digital Communication PLOS ONE, 10 (5) DOI: 10.1371/journal.pone.0122543

Nostalgia is a Muse

“Let others praise ancient times. I am glad that I was born in these.”

                                                                                                – Ovid in “Ars Amatoria”

When I struggle with scientist’s block, I play 1980s music with the hope that the music will inspire me. This blast from the past often works for me. After listening to the songs, I can sometimes perceive patterns between our various pieces of cell biology and molecular biology data that had previously eluded me and design new biological experiments. But I have to admit that I have never performed the proper music control studies. Before attributing inspirational power to songs such as “99 Luftballons“, “Bruttosozialprodukt” or “Billie Jean“, I ought to spend equal time listening to music from other decades and then compare the impact of these listening sessions. I have always assumed that there is nothing intrinsically superior or inspirational about these songs, they simply evoke memories of my childhood. Eating comfort foods or seeing images of Munich and Lagos that remind me of my childhood also seem to work their muse magic.

Camera nostalgia

My personal interpretation has been that indulging nostalgia somehow liberates us from everyday issues and worries – some trivial, some more burdensome – which in turn allows us to approach our world with a fresh, creative perspective. It is difficult to make such general sweeping statements based on my own anecdotal experiences and I have always felt a bit of apprehension about discussing this with others. My nostalgia makes me feel like an old fogey who is stuck in an ossified past. Nostalgia does not have a good reputation. The German expression “Früher war alles besser!” (Back then, everything used to be better!) is used in contemporary culture to mock those who always speak of the romanticized past with whimsical fondness. In fact, the expression nostalgia was coined in 1688 by the Swiss medical student Johannes Hofer. In his dissertation “Dissertatio Medica de Nostalgia oder Heimweh“, Hofer used nostalgia as an equivalent of the German word Heimweh (“home-ache”), combining the Greek words nostos(homecoming) and algos (ache or pain), to describe a medical illness characterized by a “melancholy that originates from the desire to return to one’s homeland“. This view of nostalgia as an illness did not change much during the subsequent centuries where it was viewed as a neurological or psychiatric disorder.

This view has been challenged by the University of Southampton researchers Constantine Sedikides and Tim Wildschut, who have spent the past decade studying the benefits of nostalgia. Not only do they disavow its disease status, they have conducted numerous studies which suggest that nostalgia can make us more creative, open-minded and charitable. The definition of nostalgia used by Sedikides and Wildschut as a “sentimental longing for one’s past” is based on the contemporary usage by laypersons across many cultures. This time-based definition of nostalgia also represents a departure from its original geographical or cultural coinage by Hofer who viewed it as a longing for the homeland and not one’s personal past.

In one of their most recent experiments, Sedikides and Wildschut investigate nostalgia as a “mnemonic muse“. The researchers first evoked nostalgic memories in participants with the following prompt:

“Please think of a nostalgic event in your life. Specifically, try to think of a past event that makes you feel most nostalgic. Bring this nostalgic experience to mind. Immerse yourself in the nostalgic experience. How does it make you feel?”

Importantly, each experiment also involved a control group of participants who were given a very different prompt:

“Please bring to mind an ordinary event in your life. Specifically, try to think of a past event that is ordinary. Bring this ordinary experience to mind. Immerse yourself in the ordinary experience. How does it make you feel?”

This allowed the researchers to compare whether specifically activating nostalgia had a distinct effect from merely activating a general memory.

After these interventions, participants in the nostalgia group and in the control group were asked to write a short story involving a princess, a cat and a race car. In an additional experiment, participants finished a story starting with the sentence: “One cold winter evening, a man and a woman were alarmed by a sound coming from a nearby house“. After 30 minutes, of writing, the stories were collected and scored for the level of creativity by independent evaluators who had no knowledge of the experimental design or group that the participants belonged to. Participants who had experienced more nostalgia wrote more creative prose!

This is just one example of the dozens of studies conducted by Sedikides and Wildschut which show the benefits of nostalgia, such as providing inspiration, increasing trust towards outsiders and enhancing the willingness to donate to charities. What is the underlying mechanism for these benefits? Sedikides and Wildschut believe that our nostalgic memories provide a sense of belonging and support, which in turn helps our self-confidence and self-esteem. The comfort of our past gives us strength for our future.

Does this mean that this longing for the past is always a good thing? Not every form of nostalgia centers on personal childhood memories. For example, there is a form of ideological nostalgia expressed by groups who feel disenfranchised by the recent progress and long for days of former power and privilege. The South African sociologists van der Waal and Robbins recently described the popularity of a song about the Anglo-Boer waramong white Afrikaans-speakers in the post-Apartheid era which may have been rooted in a nostalgic affirmation of white Afrikaner identity. It is conceivable that similar forms of ideological nostalgia could be found in other cultures and states where privileged classes and races are losing ground to increased empowerment of the general population.

It is important that we distinguish between these two forms of nostalgia – personal childhood nostalgia and ideological group nostalgia – before “rehabilitating” nostalgia’s reputation. The research by Sedikides and Wildschut clearly demonstrates that nostalgia can be a powerful tool to inspire us but we have to ensure that it is not misused as am ideological or political tool to manipulate us.


1. de Diego, F. F., & Ots, C. V. (2014). Nostalgia: a conceptual history. History of psychiatry, 25(4), 404-411.

2. Sedikides, C., & Wildschut, T. (2016). Past Forward: Nostalgia as a Motivational Force. Trends in cognitive sciences (published online Feb 18, 2016)

3. van Tilburg, W. A., Sedikides, C., & Wildschut, T. (2015). The mnemonic muse: Nostalgia fosters creativity through openness to experience.Journal of Experimental Social Psychology, 59, 1-7.

4. Van der Waal, K., & Robins, S. (2011). ‘De la Rey’and the Revival of ‘Boer Heritage’: Nostalgia in the Post-apartheid Afrikaner Culture Industry. Journal of Southern African Studies, 37(4), 763-779.


Note: An earlier version of this article was first published on 3Quarksdaily.

van Tilburg, W., Sedikides, C., & Wildschut, T. (2015). The mnemonic muse: Nostalgia fosters creativity through openness to experience Journal of Experimental Social Psychology, 59, 1-7 DOI: 10.1016/j.jesp.2015.02.002

Shame on You, Shame on Me: Shame as an Evolutionary Adaptation

Can shame be good for you? We often think of shame as a shackling emotion which thwarts our individuality and creativity. A sense of shame could prevent us from choosing a partner we truly love, speaking out against societal traditions which propagate injustice or pursuing a profession that is deemed unworthy by our peers. But if shame is so detrimental, why did we evolve with this emotion? A team of researchers led by Daniel Sznycer from the Center for Evolutionary Psychology at the University of California, Santa Barbara recently published a study in the Proceedings of the National Academy of Sciences which suggests that shame is an important evolutionary adaptation. According to their research which was conducted in the United States, Israel and India, the sense of shame helps humans avoid engaging in acts that could lead to them being devalued and ostracized by their community.

A Belgian Iron 'scolds bridle' or 'branks' mask, with bell, used to publicly humiliate and punish, mainly women, for speaking out against authority, nagging, brawling with neighbors, blaspheming or lying via Wellcome Images
Credit: Wellcome Library A Belgian Iron ‘scolds bridle’ or ‘branks’ mask, with bell, used to publicly humiliate and punish, mainly women, for speaking out against authority, nagging, brawling with neighbors, blaspheming or lying via Wellcome Images

For their first experiment, the researchers enrolled participants in the USA (118 participants completed the study; mean age of 36; 53% were female) and India (155 participants completed the study, mean age of 31, 38% were female) using the online Amazon Mechanical Turk crowdsourcing platform as well as 165 participants from a university in Israel (mean age of 23; 81% female). The participants were randomly assigned to two groups and presented with 29 scenarios: The “shame group” participants were asked to rate how much shame they would experience if they lived through any given scenario and whereas the “audience group” participants were asked how negatively they would rate a third-party person of the same age and gender as the participants in an analogous scenario.

Here is a specific scenario to illustrate the study design:

Male participants in the “shame group” were asked to rate “At the wedding of an acquaintance, you are discovered cheating on your wife with a food server” on a scale ranging from 1 (no shame at all) to 7 (a lot of shame).

Female participants in the “shame group” were asked to rate “At the wedding of an acquaintance, you are discovered cheating on your husband with a food server” on a scale ranging from 1 (no shame at all) to 7 (a lot of shame).

Male participants in the “audience group”, on the other hand, were asked to rate “At the wedding of an acquaintance, he is discovered cheating on his wife with a food server” on a scale ranging from 1 (I wouldn’t view him negatively at all) to 7 (I’d view him very negatively).

Female participants in the “audience group” rated “At the wedding of an acquaintance, she is discovered cheating on her husband with a food server” on a scale ranging from 1 (I wouldn’t view her negatively at all) to 7 (I’d view her very negatively).


To give you a sense of the breadth of scenarios that the researchers used, here are some more examples:

You stole goods from a shop owned by your neighbor.

You cannot support your children economically.

You get into a fight in front of everybody and your opponent completely dominates you with punch after punch until you’re knocked out.

You receive welfare money from the government because you cannot financially support your family.

You are not generous with others.

For each of the 29 scenarios, the researchers created gender-specific “shame” and “audience” versions. The “audience group” reveals how we rate the bad behavior of others (devaluation) whereas the “shame group” provides information into how much shame we feel if we engage in that same behavior. By ensuring that participants only participated in one of the two groups, the researchers were able to get two independent scores – shame versus devaluation – for each scenario.


The key finding of this experiment was that the third-party devaluation scores were highly correlated with the shame scores in all three countries. For example, here are the mean “shame scores” for the wedding infidelity scenario indicating that people in all three countries would have experienced a lot of shame:

USA: 6.5

India: 5.7

Israel: 6.7

The devaluation scores from the third-party “audience group” suggested that people viewed the behavior very negatively:

USA: 6.4

India: 5.1

Israel: 6.6

For nearly all the scenarios, the researchers found a surprisingly strong correlation between devaluation and shame and they also found that the correlation was similarly strong in each of the surveyed countries.

The researchers then asked the question whether this correlation between personal shame and third-party negative valuation was unique to the shame emotion or whether other negative emotions such as anxiety or sadness would also correlate equally well with devaluation. This experiment was only conducted with the participants in the USA and India. The researchers found that even though the fictitious scenarios elicited some degree of anxiety and sadness in the participants, the levels of anxiety or sadness were not significantly correlated with the extent of devaluation. The researchers interpreted these results as suggesting that there is something special about shame because it tracks so closely with how bad behavior is perceived by others whereas sadness or anxiety do not.

How do these findings inform our view on the evolutionary role of shame? The researchers suggest that instead of designating shame as an “ugly” emotion, it is instead an excellent predictor of how our peers would view our behaviors and thus deter us from making bad choices that could undermine our relationships with members of our community. The strong statistical correlations between shame and negative valuation of the behaviors as well as the universality of this link in the three countries indeed support the conclusions of the researchers. However, there are also so important limitations of these studies. As with many evolutionary psychology studies, it is not easy to ascribe a direct cause-effect relationship based on a correlation. Does devaluation lead to evolving a shame mechanism or is it perhaps the other way around? Does a sense of shame lead to a societal devaluation of certain behaviors such as dishonesty? It is also possible that the participants in the audience group responded with the concept of “shame” in the back of their mind even though they were not asked to directly comment on how shameful the act was. Perhaps their third-party assessments of how bad the behavior was were clouded by their own perceptions of how shameful the behavior would be if they themselves had engaged in it.

Another limitation of the study is that the participants represented a young subgroup of society. The mean ages of 23 (Israel), 31 (India) and 36 (USA) as well as the use of an online Amazon Mechanical Turk questionnaire means that the study results predominantly reflect the views of Millennials. The similarities of the shame and devaluation scores in three distinct cultures are among the most remarkable findings of these studies. However, perhaps they are more reflective of a global convergence of values among the Millennial generation than an underlying evolutionary conservation of an adaptive mechanism.

These limitations should not detract from the provocative questions raised by the studies. They force us to rethink how we view shame. Like all adaptive defense mechanisms, shame could go awry. Our immune function, for example, is an essential defense mechanism but an unfettered immune response can destroy the very body it is trying to protect. Perhaps shame acts in a similar fashion. A certain level of shame could help us function in society by promoting certain moral values such as justice, honesty or generosity. But an excess of shame may become a maladaptive prison which compromises our individuality.



Daniel Sznycer, John Tooby, Leda Cosmides, Roni Porat, Shaul Shalvi, and Eran Halperin. (2016). “Shame closely tracks the threat of devaluation by others, even across culturesProceedings of the National Academy of Sciences

Sznycer D, Tooby J, Cosmides L, Porat R, Shalvi S, & Halperin E (2016). Shame closely tracks the threat of devaluation by others, even across cultures. Proceedings of the National Academy of Sciences of the United States of America PMID: 26903649


Note: An earlier version of this article was first published on the 3Quarksdaily blog.

We Have Become Exhausted Slaves in a Culture of Positivity

We live in an era of exhaustion and fatigue, caused by an incessant compulsion to perform. This is one of the central tenets of the book “Müdigkeitsgesellschaft” (translatable as “The Fatigue Society” or “The Tiredness Society“) by the German philosopher Byung-Chul Han. Han is a professor at the Berlin Universität der Künste (University of the Arts) and one of the most widely read contemporary philosophers in Germany. He was born in Seoul where he studied metallurgy before he moved to Germany in the 1980s to pursue a career in philosophy. His doctoral thesis and some of his initial work in the 1990s focused on Heidegger but during the past decade, Han has written about broad range of topics regarding contemporary culture and society. “Müdigkeitsgesellschaft” was first published in 2010 and helped him attain a bit of a rock-star status in Germany despite his desire to avoid too much public attention – unlike some of his celebrity philosopher colleagues.


The book starts out with two biomedical metaphors to describe the 20th century and the emerging 21st century. For Han, the 20th century was an “immunological” era. He uses this expression because infections with viruses and bacteria which provoked immune responses were among the leading causes of disease and death and because the emergence of vaccinations and antibiotics helped conquer these threats. He then extends the “immunological” metaphor to political and societal events. Just like the immune system recognizes bacteria and viruses as “foreign” that needs to be eliminated to protect the “self”, the World Wars and the Cold War were also characterized by a clear delineation of “Us” versus “Them”. The 21stcentury, on the other hand, is a “neuronal” era characterized by neuropsychiatric diseases such as depression, attention deficit hyperactivity disorder (ADHD), burnout syndrome and borderline personality disorder. Unlike the diseases in the immunological era, where there was a clear distinction between the foreign enemy microbes that needed to be eliminated and the self, these “neuronal” diseases make it difficult to assign an enemy status. Who are the “enemies” in burnout syndrome or depression? Our environment? Our employers? Our own life decisions and choices? Are we at war with ourselves in these “neuronal” conditions? According to Han, this biomedical shift in diseases is mirrored by a political shift in a globalized world where it becomes increasingly difficult to define the “self” and the “foreign”. We may try to assign a “good guy” and “bad guy” status to navigate our 21st century but we also realize that we are so interconnected that these 20th century approaches are no longer applicable.

The cell biologist in me cringed when I read Han’s immunologic and neuronal metaphors. Yes, it is true that successfully combatting infectious diseases constituted major biomedical victories in the 20th century but these battles are far from over. The recent Ebola virus scare, the persistence of malaria resistance, the under-treatment of HIV and the emergence of multi-drug resistant bacteria all indicate that immunology and infectious disease will play central roles in the biomedical enterprise of the 21st century. The view that the immune system clearly distinguishes between “self” and “foreign” is also overly simplistic because it ignores that autoimmune diseases, many of which are on the rise and for which we still have very limited treatment options, are immunological examples of where the “self” destroys itself. Even though I agree that neuroscience will likely be the focus of biomedical research, it seems like an odd choice to select a handful of psychiatric illnesses as representing the 21st century while ignoring major neuronal disorders such as Alzheimer’s dementia, stroke or Parkinson’s disease. He also conflates specific psychiatric illnesses with the generalized increase in perceived fatigue and exhaustion.

Once we move past these ill- chosen biomedical examples, Han’s ideas become quite fascinating. He suggests that the reason why we so often feel exhausted and fatigued is because we are surrounded by a culture of positivity. At work, watching TV at home or surfing the web, we are inundated by not-so-subtle messages of what we can do. Han quotes the example of the “Yes We Can” slogan from the Obama campaign. “Yes We Can” exudes positivity by suggesting that all we need to do is try harder and that there may be no limits to what we could achieve. The same applies to the Nike “Just Do It” slogan and the thousands of self-help books published each year which reinforce the imperative of positive thinking and positive actions.

Here is the crux of Han’s thesis. “Yes We Can” sounds like an empowering slogan, indicating our freedom and limitless potential. But according to Han, this is an illusory freedom because the message enclosed within “Yes We Can” is “Yes We Should”. Instead of living in a Disziplinargesellschaft(disciplinary society) of the past where our behavior was clearly regulated by societal prohibitions and commandments, we now live in a Leistungsgesellschaft (achievement society) in which we voluntarily succumb to the pressure of achieving. The Leistungsgesellschaft is no less restrictive than the Disziplinargesellschaft. We are no longer subject to exogenous prohibitions but we have internalized the mandates of achievement, always striving to do more. We have become slaves to the culture of positivity, subjugated by the imperative “Yes, We Should”. Instead of carefully contemplating whether or not to pursue a goal, the mere knowledge that we could achieve it forces us to strive towards that goal. Buying into the “Yes We Can” culture chains us to a life of self-exploitation and we are blinded by passion and determination until we collapse. Han uses the sad German alliteration “Erschöpfung, Ermüdung und Erstickung” (“exhaustion, fatigue and suffocation”) to describe the impact that an excess of positivity has once we forgo our ability to say “No!” to the demands of the achievement society. We keep on going until our minds and bodies shut down and this is why we live in a continuous state of exhaustion and fatigue. Han does not view multitasking as a sign of civilizational progress. Multitasking is an indicator of regression because it results in a broad but rather superficial state of attention and thus prevents true contemplation

It is quite easy for us to relate to Han’s ideas at our workplace. Employees with a “can-do” attitude are praised but you will rarely see a plaque awarded to commemorate an employee’s “can-contemplate” attitude. In an achievement society, employers no longer have to exploit us because we willingly take on more and more tasks to prove our own self-worth.

While reading Han’s book, I was reminded of a passage in Bertrand Russell’s essay “In Praise of Idleness” in which he extols the virtues of reducing our workload to just four hours a day:

In a world where no one is compelled to work more than four hours a day, every person possessed of scientific curiosity will be able to indulge it, and every painter will be able to paint without starving, however excellent his pictures may be. Young writers will not be obliged to draw attention to themselves by sensational pot-boilers, with a view to acquiring the economic independence needed for monumental works, for which, when the time at last comes, they will have lost the taste and capacity. Men who, in their professional work, have become interested in some phase of economics or government, will be able to develop their ideas without the academic detachment that makes the work of university economists often seem lacking in reality. Medical men will have the time to learn about the progress of medicine, teachers will not be exasperatedly struggling to teach by routine methods things which they learnt in their youth, which may, in the interval, have been proved to be untrue.

Above all, there will be happiness and joy of life, instead of frayed nerves, weariness, and dyspepsia. The work exacted will be enough to make leisure delightful, but not enough to produce exhaustion. Since men will not be tired in their spare time, they will not demand only such amusements as are passive and vapid. At least one per cent will probably devote the time not spent in professional work to pursuits of some public importance, and, since they will not depend upon these pursuits for their livelihood, their originality will be unhampered, and there will be no need to conform to the standards set by elderly pundits. But it is not only in these exceptional cases that the advantages of leisure will appear. Ordinary men and women, having the opportunity of a happy life, will become more kindly and less persecuting and less inclined to view others with suspicion.

While Russell’s essay proposes reduction of work hours as a solution, Han’s critique of the achievement society and its impact on generalized fatigue and malaise is not limited to our workplace. By accepting the mandate of continuous achievement and hyperactivity, we apply this approach even to our leisure time. Whether it is counting the steps we walk with our fitness activity trackers or competitively racking up museum visits as a tourist, our obsession with achievement permeates all aspects of our lives. Is there a way out of this vicious cycle of excess positivity and persistent exhaustion? We need to be mindful of our right to refuse. Instead of piling on tasks for ourselves during work and leisure we need to recognize the value and strength of saying “No”. Han introduces the concept of “heilende Müdigkeit” (healing tiredness), suggesting that there is a form of tiredness that we should welcome because it is an opportunity for rest and regeneration. Weekend days are often viewed as days reserved for chores and leisure tasks that we are unable to pursue during regular workdays. By resurrecting the weekend as the time for actual rest, idleness and contemplation we can escape from the cycle of exhaustion. We have to learn not-doing in a world obsessed with doing.

Notes: An earlier version of this article was first published on the 3Quarksdaily Blog. Müdigkeitsgesellschaft was translated into English in 2015 and is available as “The Burnout Society” by Stanford University Press.

Byung-Chul Han (2015). The Burnout Society Stanford University Press

Feel Our Pain: Empathy and Moral Behavior

“It’s empathy that makes us help other people. It’s empathy that makes us moral.” The economist Paul Zak casually makes this comment in his widely watched TED talk about the hormone oxytocin, which he dubs the “moral molecule”. Zak quotes a number of behavioral studies to support his claim that oxytocin increases empathy and trust, which in turn increases moral behavior. If all humans regularly inhaled a few puffs of oxytocin through a nasal spray, we could become more compassionate and caring. It sounds too good to be true. And recent research now suggests that this overly simplistic view of oxytocin, empathy and morality is indeed too good to be true.


Many scientific studies support the idea that oxytocin is a major biological mechanism underlying the emotions of empathy and the formation of bonds between humans. However, inferring that these oxytocin effects in turn make us more moral is a much more controversial statement. In 2011, the researcher Carsten De Dreu and his colleagues at the University of Amsterdam in the Netherlands published the study Oxytocin promotes human ethnocentrism which studied indigenous Dutch male study subjects who in a blinded fashion self-administered either nasal oxytocin or a placebo spray. The subjects then answered questions and performed word association tasks after seeing photographic images of Dutch males (the “in-group”) or images of Arabs and Germans, the “out-group” because prior surveys had shown that the Dutch public has negative views of both Arabs/Muslims and Germans. To ensure that the subjects understood the distinct ethnic backgrounds of the target people shown in the images, they were referred to typical Dutch male names, German names (such as Markus and Helmut) or Arab names (such as Ahmed and Youssef).

Oxytocin increased favorable views and word associations but only towards in-group images of fellow Dutch males. The oxytocin treatment even had the unexpected effect of worsening the views regarding Arabs and Germans but this latter effect was not quite statistically significant. Far from being a “moral molecule”, oxytocin may actually increase ethnic bias in society because it selectively enhances certain emotional bonds. In a subsequent study, De Dreu then addressed another aspect of the purported link between oxytocin and morality by testing the honesty of subjects. The study Oxytocin promotes group-serving dishonesty showed that oxytocin increased cheating in study subjects if they were under the impression that dishonesty would benefit their group. De Dreu concluded that oxytocin does make us less selfish and care more about the interest of the group we belong to.

These recent oxytocin studies not only question the “moral molecule” status of oxytocin but raise the even broader question of whether more empathy necessarily leads to increased moral behavior, independent of whether or not it is related to oxytocin. The researchers Jean Decety and Jason Cowell at the University of Chicago recently analyzed the scientific literature on the link between empathy and morality in their commentary Friends or Foes: Is Empathy Necessary for Moral Behavior?, and find that the relationship is far more complicated than one would surmise. Judges, police officers and doctors who exhibit great empathy by sharing in the emotional upheaval experienced by the oppressed, persecuted and severely ill always end up making the right moral choices – in Hollywood movies. But empathy in the real world is a multi-faceted phenomenon and we use this term loosely, as Decety and Cowell point out, without clarifying which aspect of empathy we are referring to.

Decety and Cowell distinguish at least three distinct aspects of empathy:

1. Emotional sharing, which refers to how one’s emotions respond to the emotions of those around us. Empathy enables us to “feel” the pain of others and this phenomenon of emotional sharing is also commonly observed in non-human animals such as birds or mice.

2. Empathic concern, which describes how we care for the welfare of others. Whereas emotional sharing refers to how we experience the emotions of others, empathic concern motivates us to take actions that will improve their welfare. As with emotional sharing, empathic concern is not only present in humans but also conserved among many non-human species and likely constitutes a major evolutionary advantage.

3. Perspective taking, which – according to Decety and Cowell – is the ability to put oneself into the mind of another and thus imagine what they might be thinking or feeling. This is a more cognitive dimension of empathy and essential for our ability to interact with fellow human beings. Even if we cannot experience the pain of others, we may still be able to understand or envision how they might be feeling. One of the key features of psychopaths is their inability to experience the emotions of others. However, this does not necessarily mean that psychopaths are unable to cognitively imagine what others are thinking. Instead of labeling psychopaths as having no empathy, it is probably more appropriate to specifically characterize them as having a reduced capacity to share in the emotions while maintaining an intact capacity for perspective-taking.

In addition to the complexity of what we call “empathy”, we need to also understand that empathy is usually directed towards specific individuals and groups. De Dreu’s studies demonstrated that oxytocin can make us more pro-social as long as it benefits those who we feel belong to our group but not necessarily those outside of our group. The study Do you feel my pain? Racial group membership modulates empathic neural responses by Xu and colleagues at Peking University used fMRI brain imaging in Chinese and Caucasian study subjects and measured their neural responses to watching painful images. The study subjects were shown images of either a Chinese or a Caucasian face. In the control condition, the depicted image showed a face being poked with a cotton swab. In the pain condition, study subjects were shown a face of a person being poked with a needle attached to syringe. When the researchers measured the neural responses with the fMRI, they found significant activation in the anterior cingulate cortex (ACC) which is part of the neural pain circuit, both for pain we experience ourselves but also for empathic pain we experience when we see others in pain. The key finding in Xu’s study was that ACC activation in response to seeing the painful image was much more profound when the study subject and the person shown in the painful image belonged to the same race.

As we realize that the neural circuits and hormones which form the biological basis of our empathy responses are so easily swayed by group membership then it becomes apparent why increased empathy does not necessarily result in behavior consistent with moral principles. In his essay “Against Empathy“, the psychologist Paul Bloom also opposes the view that empathy should form the basis of morality and that we should unquestioningly elevate empathy to virtue for all:

“But we know that a high level of empathy does not make one a good person and that a low level does not make one a bad person. Being a good person likely is more related to distanced feelings of compassion and kindness, along with intelligence, self-control, and a sense of justice. Being a bad person has more to do with a lack of regard for others and an inability to control one’s appetites.”

I do not think that we can dismiss empathy as a factor in our moral decision-making. Bloom makes a good case for distanced compassion and kindness that does not arise from the more visceral emotion of empathy. But when we see fellow humans and animals in pain, then our initial biological responses are guided by empathy and anger, not the more abstract concept of distanced compassion. What we need is a better scientific and philosophical understanding of what empathy is. Empathic perspective-taking may be a far more robust and reliable guide for moral decision-making than empathic emotions. Current scientific studies on empathy often measure it as an aggregate measure without teasing out the various components of empathy. They also tend to underestimate that the relative contributions of the empathy components (emotion, concern, perspective-taking) can vary widely among cultures and age groups. We need to replace overly simplistic notions such as oxytocin = moral molecule or empathy = good with a more refined view of the complex morality-empathy relationship guided by rigorous science and philosophy.



De Dreu, C. K., Greer, L. L., Van Kleef, G. A., Shalvi, S., & Handgraaf, M. J. (2011). Oxytocin promotes human ethnocentrismProceedings of the National Academy of Sciences, 108(4), 1262-1266.

Decety, J., & Cowell, J. M. (2014). Friends or Foes: Is Empathy Necessary for Moral Behavior?Perspectives on Psychological Science, 9(5), 525-537.

Shalvi, S., & De Dreu, C. K. (2014). Oxytocin promotes group-serving dishonestyProceedings of the National Academy of Sciences, 111(15), 5503-5507.

Xu, X., Zuo, X., Wang, X., & Han, S. (2009). Do you feel my pain? Racial group membership modulates empathic neural responsesThe Journal of Neuroscience, 29(26), 8525-8529.



Note: An earlier version of this article was first published on the 3Quarksdaily blog.





De Dreu, C., Greer, L., Van Kleef, G., Shalvi, S., & Handgraaf, M. (2011). Oxytocin promotes human ethnocentrism Proceedings of the National Academy of Sciences, 108 (4), 1262-1266 DOI: 10.1073/pnas.1015316108


Decety J, & Cowell JM (2014). Friends or Foes: Is Empathy Necessary for Moral Behavior? Perspectives on psychological science : a journal of the Association for Psychological Science, 9 (5), 525-37 PMID: 25429304


Shalvi S, & De Dreu CK (2014). Oxytocin promotes group-serving dishonesty. Proceedings of the National Academy of Sciences of the United States of America, 111 (15), 5503-7 PMID: 24706799


Xu X, Zuo X, Wang X, & Han S (2009). Do you feel my pain? Racial group membership modulates empathic neural responses. The Journal of neuroscience : the official journal of the Society for Neuroscience, 29 (26), 8525-9 PMID: 19571143

The Long Shadow of Nazi Indoctrination: Persistence of Anti-Semitism in Germany

Anti-Semitism and the holocaust are among the central themes in the modern German secondary school curriculum. During history lessons in middle school, we learned about anti-Semitism and the persecution of Jews in Europe during the middle ages and early modernity. Our history curriculum in the ninth and tenth grades focused on the virulent growth of anti-Semitism in 20th century Europe, how Hitler and the Nazi party used anti-Semitism as a means to rally support and gain power, and how the Nazi apparatus implemented the systematic genocide of millions of Jews.

Image of a Hitler Youth meeting from the German Federal Archive via Wikimedia
Image of a Hitler Youth meeting from the German Federal Archive via Wikimedia

In grades 11 to 13, the educational focus shifts to a discussion of the broader moral and political context of anti-Semitism and Nazism. How could the Nazis enlist the active and passive help of millions of “upstanding” citizens to participate in this devastating genocide? Were all Germans who did not actively resist the Nazis morally culpable or at least morally responsible for the Nazi horrors? Did Germans born after the Second World War inherit some degree of moral responsibility for the crimes committed by the Nazis? How can German society ever redeem itself after being party to the atrocities of the Nazis? Anti-Semitism and Nazism were also important topics in our German literature and art classes because the Nazis persecuted and murdered German Jewish intellectuals and artists, and because the shame and guilt experienced by Germans after 1945 featured so prominently in German art and literature.

One purpose of extensively educating Germany school-children about  this dark and shameful period of German history is the hope that if they are ever faced with the reemergence of prejudice directed against Jews or any other ethnic or religious group, they will have the courage to stand up for those who are being persecuted and make the right moral choices. As such, it is part of the broader Vergangenheitsbewältigung (wrestling with one’s past) in post-war German society which takes place not only in schools but in various public venues. The good news, according to recent research published in the Proceedings of the National Academy of Sciences by Nico Voigtländer and Hans-Joachim Voth, is that Germans who attended school after the Second World War have shown a steady decline in anti-Semitism. The bad news: Vergangenheitsbewältigung is a bigger challenge for Germans who attended school under the Nazis because a significant proportion of them continue to exhibit high levels of anti-Semitic attitudes more than half a century after the defeat of Nazi Germany.

Voigtländer and Voth examined the results of the large General Social Survey for Germany (ALLBUS) in which several thousand Germans were asked about their values and beliefs. The survey took place in 1996 and 2006, and the researchers combined the results of both surveys with a total of 5,300 participants from 264 German towns and cities. The researchers were specifically interested in anti-Semitic attitudes and focused on three survey questions specifically related to anti-Semitism. Survey participants were asked to respond on a scale of 1 to 7 and indicate whether they thought Jews had too much influence in the world, whether Jews were responsible for their own persecution and whether Jews should have equal rights. The researchers categorized participants as “committed anti-Semites” if they revealed anti-Semitic attitudes to all three questions. The overall rate of committed anti-Semites was 4% in Germany but there was significant variation depending on the geographical region and the age of the participants.

Germans born in the 1970s and 1980s had only 2%-3% committed anti-Semites whereas the rate was nearly double for Germans born in the 1920s (6%). However, the researchers noted one exception: Germans born in the 1930s. Those citizens had the highest fraction of anti-Semites: 10%. The surveys were conducted in 1996 and 2006 when the participants born in in the 1930s were 60-75 years old. In other words, one out of ten Germans of that generation did not think that Jews deserved equal rights!

The researchers attributed this to the fact that people born in the 1930s were exposed to the full force of systematic Nazi indoctrination with anti-Semitic views which started as early as in elementary school and also took place during extracurricular activities such as the Hitler Youth programs. The Nazis came to power in 1933 and immediately began implementing a whole-scale propaganda program in all schools. A child born in 1932, for example, would have attended elementary school and middle school as well as Hitler Youth programs from age six onwards till the end of the war in 1945 and become inculcated with anti-Semitic propaganda.

The researchers also found that the large geographic variation in anti-Semitic prejudices today was in part due to the pre-Nazi history of anti-Semitism in any given town. The Nazis were not the only and not the first openly anti-Semitic political movement in Germany. There were German political parties with primarily anti-Jewish agendas which ran for election in the late 19th century and early 20th century. Voigtländer and Voth analyzed the votes that these anti-Semitic parties received more than a century ago, from 1890 to 1912. Towns and cities with the highest support for anti-Semitic parties in this pre-Nazi era are also the ones with the highest levels of anti-Semitic prejudice today. When children were exposed to anti-Semitic indoctrination in schools under the Nazis, the success of these hateful messages depended on how “fertile” the ground was. If the children were growing up in towns and cities where family members or public figures had supported anti-Jewish agenda during prior decades then there was a much greater likelihood that the children would internalize the Nazi propaganda. The researchers cite the memoir of the former Hitler Youth member Alfons Heck:

“We who were born into Nazism never had a chance unless our parents were brave enough to resist the tide and transmit their opposition to their children. There were few of those.”

                                    – Alfons Heck in “The Burden of Hitler’s Legacy

The researchers then address the puzzling low levels of anti-Semitic prejudices among Germans born in the 1920s. If the theory of the researcher were correct that anti-Semitic prejudices persist today because Nazi school indoctrination then why aren’t Germans born in the 1920s more anti-Semitic? A child born in 1925 would have been exposed to Nazi propaganda throughout secondary school. Oddly enough, women born in the 1920s did show high levels of anti-Semitism when surveyed in 1996 and 2006 but men did not. Voigtländer and Voth solve this mystery by reviewing wartime fatality rates. The most zealous male Nazi supporters with strong anti-Semitic prejudices were more likely to volunteer for the Waffen-SS, the military wing of the Nazi party. Some SS divisions had an average age of 18 and these SS-divisions had some of the highest fatality rates. This means that German men born in the 1920s weren’t somehow immune to Nazi propaganda. Instead, most of them perished because they bought into it and this is why we now see lower levels of anti-Semitism than expected in Germans born during that decade.

A major limitation of this study is its correlational nature and the lack of data on individual exposure to Nazism. The researchers base their conclusions on birth years and historical votes for anti-Semitic parties of towns but did not track how much individuals were exposed to anti-Semitic propaganda in their schools or their families. Such a correlational study cannot establish a cause-effect relationship between propaganda and the persistence of prejudice today. One factor not considered by the researchers, for example, is that Germans born in the 1930s are also among those who grew up as children in post-war Germany, often under conditions of extreme poverty and even starvation.

Even without being able to establish a clear cause-effect relationship, the findings of the study raise important questions about the long-term effects of racial propaganda. It appears that a decade of indoctrination may give rise to a lifetime of hatred. Our world continues to be plagued by prejudice against fellow humans based on their race or ethnicity, religion, political views, gender or sexual orientation. Children today are not subject to the systematic indoctrination implemented by the Nazis but they are probably still exposed to more subtle forms of prejudice and we do not know much about its long-term effects. We need to recognize the important role of public education in shaping the moral character of individuals and ensure that our schools help our children become critical thinkers with intact moral reasoning, citizens who can resist indoctrination and prejudice.




Voigtländer N and Voth HJ. “Nazi indoctrination and anti-Semitic beliefs in Germany” Proceedings of the National Academy of Sciences (2015), doi: 10.1073/pnas.1414822112

Voigtländer N, & Voth HJ (2015). Nazi indoctrination and anti-Semitic beliefs in Germany. Proceedings of the National Academy of Sciences of the United States of America PMID: 26080394




Note: An earlier version of this article was first published on the 3Quarksdaily Blog.

Murder Your Darling Hypotheses But Do Not Bury Them

“Whenever you feel an impulse to perpetrate a piece of exceptionally fine writing, obey it—whole-heartedly—and delete it before sending your manuscript to press. Murder your darlings.”

Sir Arthur Quiller-Couch (1863–1944). On the Art of Writing. 1916


Murder your darlings. The British writer Sir Arthur Quiller Crouch shared this piece of writerly wisdom when he gave his inaugural lecture series at Cambridge, asking writers to consider deleting words, phrases or even paragraphs that are especially dear to them. The minute writers fall in love with what they write, they are bound to lose their objectivity and may not be able to judge how their choice of words will be perceived by the reader. But writers aren’t the only ones who can fall prey to the Pygmalion syndrome. Scientists often find themselves in a similar situation when they develop “pet” or “darling” hypotheses.

Hypothesis via Shutterstock
Hypothesis via Shutterstock

How do scientists decide when it is time to murder their darling hypotheses? The simple answer is that scientists ought to give up scientific hypotheses once the experimental data is unable to support them, no matter how “darling” they are. However, the problem with scientific hypotheses is that they aren’t just generated based on subjective whims. A scientific hypothesis is usually put forward after analyzing substantial amounts of experimental data. The better a hypothesis is at explaining the existing data, the more “darling” it becomes. Therefore, scientists are reluctant to discard a hypothesis because of just one piece of experimental data that contradicts it.

In addition to experimental data, a number of additional factors can also play a major role in determining whether scientists will either discard or uphold their darling scientific hypotheses. Some scientific careers are built on specific scientific hypotheses which set apart certain scientists from competing rival groups. Research grants, which are essential to the survival of a scientific laboratory by providing salary funds for the senior researchers as well as the junior trainees and research staff, are written in a hypothesis-focused manner, outlining experiments that will lead to the acceptance or rejection of selected scientific hypotheses. Well written research grants always consider the possibility that the core hypothesis may be rejected based on the future experimental data. But if the hypothesis has to be rejected then the scientist has to explain the discrepancies between the preferred hypothesis that is now falling in disrepute and all the preliminary data that had led her to formulate the initial hypothesis. Such discrepancies could endanger the renewal of the grant funding and the future of the laboratory. Last but not least, it is very difficult to publish a scholarly paper describing a rejected scientific hypothesis without providing an in-depth mechanistic explanation for why the hypothesis was wrong and proposing alternate hypotheses.

For example, it is quite reasonable for a cell biologist to formulate the hypothesis that protein A improves the survival of neurons by activating pathway X based on prior scientific studies which have shown that protein A is an activator of pathway X in neurons and other studies which prove that pathway X improves cell survival in skin cells. If the data supports the hypothesis, publishing this result is fairly straightforward because it conforms to the general expectations. However, if the data does not support this hypothesis then the scientist has to explain why. Is it because protein A did not activate pathway X in her experiments? Is it because in pathway X functions differently in neurons than in skin cells? Is it because neurons and skin cells have a different threshold for survival? Experimental results that do not conform to the predictions have the potential to uncover exciting new scientific mechanisms but chasing down these alternate explanations requires a lot of time and resources which are becoming increasingly scarce. Therefore, it shouldn’t come as a surprise that some scientists may consciously or subconsciously ignore selected pieces of experimental data which contradict their darling hypotheses.

Let us move from these hypothetical situations to the real world of laboratories. There is surprisingly little data on how and when scientists reject hypotheses, but John Fugelsang and Kevin Dunbar at Dartmouth conducted a rather unique study “Theory and data interactions of the scientific mind: Evidence from the molecular and the cognitive laboratory” in 2004 in which they researched researchers. They sat in at scientific laboratory meetings of three renowned molecular biology laboratories at carefully recorded how scientists presented their laboratory data and how they would handle results which contradicted their predictions based on their hypotheses and models.

In their final analysis, Fugelsang and Dunbar included 417 scientific results that were presented at the meetings of which roughly half (223 out of 417) were not consistent with the predictions. Only 12% of these inconsistencies lead to change of the scientific model (and thus a revision of hypotheses). In the vast majority of the cases, the laboratories decided to follow up the studies by repeating and modifying the experimental protocols, thinking that the fault did not lie with the hypotheses but instead with the manner how the experiment was conducted. In the follow up experiments, 84 of the inconsistent findings could be replicated and this in turn resulted in a gradual modification of the underlying models and hypotheses in the majority of the cases. However, even when the inconsistent results were replicated, only 61% of the models were revised which means that 39% of the cases did not lead to any significant changes.

The study did not provide much information on the long-term fate of the hypotheses and models and we obviously cannot generalize the results of three molecular biology laboratory meetings at one university to the whole scientific enterprise. Also, Fugelsang and Dunbar’s study did not have a large enough sample size to clearly identify the reasons why some scientists were willing to revise their models and others weren’t. Was it because of varying complexity of experiments and models? Was it because of the approach of the individuals who conducted the experiments or the laboratory heads? I wish there were more studies like this because it would help us understand the scientific process better and maybe improve the quality of scientific research if we learned how different scientists handle inconsistent results.

In my own experience, I have also struggled with results which defied my scientific hypotheses. In 2002, we found that stem cells in human fat tissue could help grow new blood vessels. Yes, you could obtain fat from a liposuction performed by a plastic surgeon and inject these fat-derived stem cells into animal models of low blood flow in the legs. Within a week or two, the injected cells helped restore the blood flow to near normal levels! The simplest hypothesis was that the stem cells converted into endothelial cells, the cell type which forms the lining of blood vessels. However, after several months of experiments, I found no consistent evidence of fat-derived stem cells transforming into endothelial cells. We ended up publishing a paper which proposed an alternative explanation that the stem cells were releasing growth factors that helped grow blood vessels. But this explanation was not as satisfying as I had hoped. It did not account for the fact that the stem cells had aligned themselves alongside blood vessel structures and behaved like blood vessel cells.

Even though I “murdered” my darling hypothesis of fat –derived stem cells converting into blood vessel endothelial cells at the time, I did not “bury” the hypothesis. It kept ruminating in the back of my mind until roughly one decade later when we were again studying how stem cells were improving blood vessel growth. The difference was that this time, I had access to a live-imaging confocal laser microscope which allowed us to take images of cells labeled with red and green fluorescent dyes over long periods of time. Below, you can see a video of human bone marrow mesenchymal stem cells (labeled green) and human endothelial cells (labeled red) observed with the microscope overnight. The short movie compresses images obtained throughout the night and shows that the stem cells indeed do not convert into endothelial cells. Instead, they form a scaffold and guide the endothelial cells (red) by allowing them to move alongside the green scaffold and thus construct their network. This work was published in 2013 in the Journal of Molecular and Cellular Cardiology, roughly a decade after I had been forced to give up on the initial hypothesis. Back in 2002, I had assumed that the stem cells were turning into blood vessel endothelial cells because they aligned themselves in blood vessel like structures. I had never considered the possibility that they were scaffold for the endothelial cells.

This and other similar experiences have lead me to reformulate the “murder your darlings” commandment to “murder your darling hypotheses but do not bury them”. Instead of repeatedly trying to defend scientific hypotheses that cannot be supported by emerging experimental data, it is better to give up on them. But this does not mean that we should forget and bury those initial hypotheses. With newer technologies, resources or collaborations, we may find ways to explain inconsistent results years later that were not previously available to us. This is why I regularly peruse my cemetery of dead hypotheses on my hard drive to see if there are ways of perhaps resurrecting them, not in their original form but in a modification that I am now able to test.



Fugelsang, J., Stein, C., Green, A., & Dunbar, K. (2004). Theory and Data Interactions of the Scientific Mind: Evidence From the Molecular and the Cognitive Laboratory. Canadian Journal of Experimental Psychology/Revue canadienne de psychologie expérimentale, 58 (2), 86-95 DOI: 10.1037/h0085799


Note: An earlier version of this article first appeared on 3Quarksdaily.

“She’s strong for a girl”: The Negative Impact of Stereotypes About Women

This is a guest blog post by Ulli Hain (Twitter: @ulli_hain, Email: hain.ulli[at] Ulli is a postdoctoral researcher in the field of autophagy and also a science writer/blogger. Her blog Bench and Beyond reports on interesting scientific studies and explores life as a scientist including issues of gender and science.

We have all heard the stereotypes: women can’t drive, they don’t understand computers, and how many blondes does it take to screw in a light bulb? But those are all in good fun, right? But what if gender stereotypes actually bring about the observed differences between men and women that supposedly underline these stereotypes? A recent study by the psychologist Marina Pavlova at the University of Tübingen tested this idea.


Boy and Girl at School - Stereotypes about favorites subjects. Via Shutterstock.

Boy and Girl at School – Stereotypes about favorites subjects. Via Shutterstock.


While previous studies have supported the idea that negative stereotypes hinder women’s athletic and cognitive performance on a range of tests, those studies all looked at tasks with preexisting stereotypes. For example women score worse on math tests when reminded of old “adages” about women and math.


Pavlova and her colleagues instead wanted to see how stereotype impacts an area where no gender difference exists. Could a fabricated stereotype change the way women and men perform on a test?


They chose the event arrangement (EA) test, used on certain modern IQ tests to measure nonverbal reasoning skills. Participants arrange cards depicting scenes, such as a man fishing, cooking over a campfire, and preparing for a trip, in a logical order to create a story. Scores are based on the number of correct sequences and amount of time required.


117 college students were split into three groups and given different instructions for the test. The first group was given standard instructions on the task. A second group was additionally told: “females usually perform worse on this task” while the third group was told: “males usually perform worse on this task.”


Men and women performed equally well when no stereotyped messages were given. When the group was told that women usually perform worse, women’s scores on the test decreased. In contrast, men’s scores actually increased, perhaps reflecting that their confidence was boosted by the perceived weakness of women. helped boost that they thrived on their perceived advantage.


The most surprising findings came from the group that was told that men usually do worse on the test. Men’s performance was diminished as expected, but instead of improving women’s scores, they dropped just as much as men.


Pavlova and her colleagues also looked at positive messages. Telling participants that women are usually better at the EA test modestly improved women’s scores without affecting men. However, the opposite was not true. Women’s performance was even more hurt by being told that men are better at the test than the more explicit message that women are worse.

What clearly emerges from the study is that women are more susceptible to stereotyping than men. The only time men’s performance declined was when given the explicit negative male message.


Why are women more impacted by the stereotypes than men? Although controlling for preexisting stereotypes on this specific test, researchers cannot escape society’s influence on women, which begins at an incredibly early age. Women are constantly under the threat of stereotype. And women who break stereotypes face harsh criticism not faced by men, such as criticism of working mothers who use daycare or the perception of women who speak up as being aggressive or bossy rather than being leaders.


The researchers suggest that since women have a history of being typecast, they may misinterpret the message “males are usually worse” to mean that if men have a hard time with the test, women will have an even harder time.


More and more studies confirm the existence of subtle forms of bias against women at all levels of society. It is a major finding that these subtle biases can have even greater psychological consequences than more blatant and bygone forms of sexism. Interventions are needed to combat existing stereotypes at an early age.
Pavlova, M., Weber, S., Simoes, E., & Sokolov, A. (2014). Gender Stereotype Susceptibility PLoS ONE, 9 (12) DOI: 10.1371/journal.pone.0114802

Does Thinking About God Increase Our Willingness to Make Risky Decisions?

There are at least two ways of how the topic of trust in God is broached in Friday sermons that I have attended in the United States. Some imams lament the decrease of trust in God in the age of modernity. Instead of trusting God that He is looking out for the believers, modern day Muslims believe that they can control their destiny on their own without any Divine assistance. These imams see this lack of trust in God as a sign of weakening faith and an overall demise in piety. But in recent years, I have also heard an increasing number of sermons mentioning an important story from the Muslim tradition. In this story, Prophet Muhammad asked a Bedouin why he was leaving his camel untied and thus taking the risk that this valuable animal might wander off and disappear. When the Bedouin responded that he placed his trust in God who would ensure that the animal stayed put, the Prophet told him that he still needed to first tie up his camel and then place his trust in God. Sermons referring to this story admonish their audience to avoid the trap of fatalism. Just because you trust God does not mean that it obviates the need for rational and responsible action by each individual.


It is much easier for me to identify with the camel-tying camp because I find it rather challenging to take risks exclusively based on the trust in an inscrutable and minimally communicative entity. Both, believers and non-believers, take risks in personal matters such as finance or health. However, in my experience, many believers who make a risky financial decision or take a health risk by rejecting a medical treatment backed by strong scientific evidence tend to invoke the name of God when explaining why they took the risk. There is a sense that God is there to back them up and provide some security if the risky decision leads to a detrimental outcome. It would therefore not be far-fetched to conclude that invoking the name of God may increase risk-taking behavior, especially in people with firm religious beliefs. Nevertheless, psychological research in the past decades has suggested the opposite: Religiosity and reminders of God seem to be associated with a reduction in risk-taking behavior.

Daniella Kupor and her colleagues at Stanford University have recently published the paper “Anticipating Divine Protection? Reminders of God Can Increase Nonmoral Risk Taking” which takes a new look at the link between invoking the name of God and risky behaviors. The researchers hypothesized that reminders of God may have opposite effects on varying types of risk-taking behavior. For example, risk-taking behavior that is deemed ‘immoral’ such as taking sexual risks or cheating may be suppressed by invoking God, whereas taking non-moral risks, such as making risky investments or sky-diving, might be increased because reminders of God provide a sense of security. According to Kupor and colleagues, it is important to classify the type of risky behavior in relation to how society perceives God’s approval or disapproval of the behavior. The researchers conducted a variety of experiments to test this hypothesis using online study participants.

One of the experiments involved running ads on a social media network and then assessing the rate of how often the social media users clicked on slightly different wordings of the ad texts. The researchers ran the ads 452,051 times on accounts registered to users over the age of 18 years residing in the United States. The participants either saw ads for non-moral risk-taking behavior (skydiving), moral risk-taking behavior (bribery) or a control behavior (playing video games) and each ad came either in a ‘God version’ or a standard version.

Here are the two versions of the skydiving ad (both versions had a picture of a person skydiving):

Amazing Skydiving!

God knows what you are missing! Find skydiving near you. Click here, feel the thrill!

Amazing Skydiving!

You don’t know what you are missing! Find skydiving near you. Click here, feel the thrill!

The percentage of users who clicked on the skydiving ad in the ‘God version’ was twice as high as in the group which saw the standard “You don’t know what you are missing” phrasing! One explanation for the significantly higher ad success rate is that “God knows….” might have struck the ad viewers as being rather unusual and piqued their curiosity. Instead of this being a reflection of increased propensity to take risks, perhaps the viewers just wanted to find out what was meant by “God knows…”. However, the response to the bribery ad suggests that it isn’t just mere curiosity. These are the two versions of the bribery ad (both versions had an image of two hands exchanging money):

Learn How to Bribe!

God knows what you are missing! Learn how to bribe with little risk of getting caught!

Learn How to Bribe!

You don’t know what you are missing! Learn how to bribe with little risk of getting caught!

In this case, the ‘God version’ cut down the percentage of clicks to less than half of the standard version. The researchers concluded that invoking the name of God prevented the users from wanting to find out more about bribery because they consciously or subconsciously associated bribery with being immoral and rejected by God.

These findings are quite remarkable because they suggest that a a single mention of the word ‘God’ in an ad can have opposite effects on two different types of risk-taking, the non-moral thrill of sky-diving versus the immoral risk of taking bribes.
Clicking on an ad for a potentially risky behavior is not quite the same as actually engaging in that behavior. This is why the researchers also conducted a separate study in which participants were asked to answer a set of questions after viewing certain colors. Participants could choose between Option 1 (a short 2 minute survey and receiving an additional 25 cents as a reward) or Option 2 (four minute survey, no additional financial incentive). The participants were also informed that Option 1 was more risky with the following label:


Eye Hazard: Option 1 not for individuals under 18. The bright colors in this task may damage the retina and cornea in the eyes. In extreme cases it can also cause macular degeneration.

In reality, neither of the two options was damaging to the eyes of the participants but the participants did not know this. This set-up allowed the researchers to assess the likelihood of the participants taking the risk of potentially injurious light exposure to their eyes. To test the impact of God reminders, the researchers assigned the participants to read one of two texts, both of which were adapted from Wikipedia, before deciding on Option 1 or Option 2:

Text used for participants in the control group:

“In 2006, the International Astronomers’ Union passed a resolution outlining three conditions for an object to be called a planet. First, the object must orbit the sun; second, the object must be a sphere; and third, it must have cleared the neighborhood around its orbit. Pluto does not meet the third condition, and is thus not a planet.”


Text used for the participants in the ‘God reminder’ group:

“God is often thought of as a supreme being. Theologians have described God as having many attributes, including omniscience (infinite knowledge), omnipotence (unlimited power), omnipresence (present everywhere), and omnibenevolence (perfect goodness). God has also been conceived as being incorporeal (immaterial), a personal being, and the “greatest conceivable existent.”

As hypothesized by the researchers, a significantly higher proportion of participants chose the supposedly harmful Option 1 in the ‘God reminder’ group (96%) than in the control group (84%). Reading a single paragraph about God’s attributes was apparently sufficient to lull more participants into the risk of exposing their eyes to potential harm. The overall high percentage of participants choosing Option 1 even in the control condition is probably due to the fact that it offered a greater financial reward (although it seems a bit odd that participants were willing to sell out their retinas for a quarter, but maybe they did not really take the risk very seriously).
A limitation of the study is that it does not provide any information on whether the impact of mentioning God was dependent on the religious beliefs of the participants. Do ‘God reminders’ affect believers as well atheists and agnostics or do they only work in people who clearly identify with a religious tradition? Another limitation is that even though many of the observed differences between the ‘God condition’ and the control conditions were statistically significant, the actual differences in numbers were less impressive. For example, in the sky-diving ad experiment, the click-through rate was about 0.03% in the standard ad and 0.06% in the ‘God condition’. This is a doubling but how meaningful is this doubling when the overall click rates are so low? Even the difference between the two groups who read the Wikipedia texts and chose Option 1 (96% vs. 84%) does not seem very impressive. However, one has to bear in mind that all of these interventions were very subtle – inserting a single mention of God into a social media ad or asking participants to read a single paragraph about God.

People who live in societies which are suffused with religion such as the United States or Pakistan are continuously reminded of God, whether they glance at their banknotes, turn on the TV or take a pledge of allegiance in school. If the mere mention of God in an ad can already sway some of us to increase our willingness to take risks, what impact does the continuous barrage of God mentions have on our overall risk-taking behavior? Despite its limitations, the work by Kupor and colleagues provides a fascinating new insight on the link between reminders of God and risk-taking behavior. By demonstrating the need to replace blanket statements regarding the relationship between God, religiosity and risk-taking with a more subtle distinction between moral and non-moral risky behaviors, the researchers are paving the way for fascinating future studies on how religion and mentions of God influence human behavior and decision-making.



Kupor DM, Laurin L, Levav J. “Anticipating Divine Protection? Reminders of God Can Increase Nonmoral Risk Taking” Psychological Science (2015) doi: 10.1177/0956797614563108


Note: An earlier version of this article was first published on the 3Quarksdaily Blog.

Typical Dreams: A Comparison of Dreams Across Cultures

But I, being poor, have only my dreams;

I have spread my dreams under your feet;

Tread softly because you tread on my dreams.

                                    William Butler Yeats – from “Aedh Wishes for the Cloths of Heaven


Mysterious maze via Shutterstock
Mysterious maze via Shutterstock



Have you ever wondered how the content of your dreams differs from that of your friends? How about the dreams of people raised in different countries and cultures? It is not always easy to compare dreams of distinct individuals because the content of dreams depends on our personal experiences. This is why dream researchers have developed standardized dream questionnaires in which common thematic elements are grouped together. These questionnaires can be translated into various languages and used to survey and scientifically analyze the content of dreams. Open-ended questions about dreams might elicit free-form, subjective answers which are difficult to categorize and analyze. Therefore, standardized dream questionnaires ask study subjects “Have you ever dreamed of . . .” and provide research subjects with a list of defined dream themes such as being chased, flying or falling.

Dream researchers can also modify the questionnaires to include additional questions about the frequency or intensity of each dream theme and specify the time frame that the study subjects should take into account. For example, instead of asking “Have you ever dreamed of…”, one can prompt subjects to focus on the dreams of the last month or the first memory of ever dreaming about a certain theme. Any such subjective assessment of one’s dreams with a questionnaire has its pitfalls. We routinely forget most of our dreams and we tend to remember the dreams that are either the most vivid or frequent, as well as the dreams which we may have discussed with friends or written down in a journal. The answers to dream questionnaires may therefore be a reflection of our dream memory and not necessarily the actual frequency of prevalence of certain dream themes. Furthermore, standardized dream questionnaires are ideal for research purposes but may not capture the complex and subjective nature of dreams. Despite these pitfalls, research studies using dream questionnaires provide a fascinating insight into the dream world of large groups of people and identify commonalities or differences in the thematic content of dreams across cultures.

The researcher Calvin Kai-Ching Yu from the Hong Kong Shue Yan University used a Chinese translation of a standardized dream questionnaire and surveyed 384 students at the University of Hong Kong (mostly psychology students; 69% female, 31% male; mean age 21). Here are the results:

Ten most prevalent dream themes in a sample of Chinese students according to Yu (2008):

  1. Schools, teachers, studying (95%)
  2. Being chased or pursued (92 %)
  3. Falling (87 %)
  4. Arriving too late, e.g., missing a train (81 %)
  5. Failing an examination (79 %)
  6. A person now alive as dead (75%)
  7. Trying again and again to do something (74%)
  8. Flying or soaring through the air (74%)
  9. Being frozen with fright (71 %)
  10. Sexual experiences (70%)

The most prevalent theme was “Schools, teachers, studying“. This means that 95% of the study subjects recalled having had dreams related to studying, school or teachers at some point in their lives, whereas only 70% of the subjects recalled dreams about sexual experiences. The subjects were also asked to rank the frequency of the dreams on a 5-point scale (0 = never, 1=seldom, 2= sometimes, 3= frequently, 4= very frequently). For the most part, the most prevalent dreams were also the most frequent ones. Not only did nearly every subject recall dreams about schools, teachers or studying, this theme also received an average frequency score of 2.3, indicating that for most individuals this was a recurrent dream theme – not a big surprise in university students. On the other hand, even though the majority of subjects (57%) recalled dreams of “being smothered, unable to breathe“, its average frequency rating was low (0.9), indicating that this was a rare (but probably rather memorable) dream.

How do the dreams of the Chinese students compare to their counterparts in other countries?

Michael Schredl and his colleagues used a similar questionnaire to study the dreams of German university students (nearly all psychology students; 85% female, 15% male; mean age 24) with the following results:

Ten most prevalent dream themes in a sample of German students according to Schredl and colleagues (2004):

  1. Schools, teachers, studying (89 %)
  2. Being chased or pursued (89%)
  3. Sexual experiences (87 %)
  4. Falling (74 %)
  5. Arriving too late, e.g., missing a train (69 %)
  6. A person now alive as dead (68 %)
  7. Flying or soaring through the air (64%)
  8. Failing an examination (61 %)
  9. Being on the verge of falling (57 %)
  10. Being frozen with fright (56 %)

There is a remarkable overlap in the top ten list of dream themes among Chinese and German students. Dreams about school and about being chased are the two most prevalent themes for Chinese and German students. One key difference is that dreams about sexual experiences are recalled more commonly among German students.

Tore Nielsen and his colleagues administered a dream questionnaire to students at three Canadian universities, thus obtaining data on an even larger study population (over 1,000 students).

Ten most prevalent dream themes in a sample of Canadian students according to Nielsen and colleagues (2003):

  1. Being chased or pursued (82 %)
  2. Sexual experiences (77 %)
  3. Falling (74 %)
  4. Schools, teachers, studying (67 %)
  5. Arriving too late, e.g., missing a train (60 %)
  6. Being on the verge of falling (58 %)
  7. Trying again and again to do something (54 %)
  8. A person now alive as dead (54 %)
  9. Flying or soaring through the air (48%)
  10. Vividly sensing . . . a presence in the room (48 %)

It is interesting that dreams about school or studying were the most common theme among Chinese and German students but do not even make the top-three list among Canadian students. This finding is perhaps also mirrored in the result that dreams about failing exams are comparatively common in Chinese and German students, but are not found in the top-ten list among Canadian students.

At first glance, the dream content of German students seems to be somehow a hybrid between those of Chinese and Canadian students. Chinese and German students share a higher prevalence of academia-related dreams, whereas sexual dreams are among the most prevalent dreams for both Canadians and Germans. However, I did notice an interesting aberrancy. Chinese and Canadian students dream about “Trying again and again to do something” – a theme which is quite rare among German students. I have simple explanation for this (possibly influenced by the fact that I am German): Germans get it right the first time which is why they do not dream about repeatedly attempting the same task.

The strength of these three studies is that they used similar techniques to assess dream content and evaluated study subjects with very comparable backgrounds: Psychology students in their early twenties. This approach provides us with the unique opportunity to directly compare and contrast the dreams of people who were raised on three continents and immersed in distinct cultures and languages. However, this approach also comes with a major limitation. We cannot easily extrapolate these results to the general population. Dreams about studying and school may be common among students but they are probably rare among subjects who are currently holding a full-time job or are retired. University students are an easily accessible study population but they are not necessarily representative of the society they grow up in. Future studies which want to establish a more comprehensive cross-cultural comparison of dream content should probably attempt to enroll study subjects of varying ages, professions, educational and socio-economic backgrounds.

Despite its limitation, the currently available data on dream content comparisons across countries does suggest one important message: People all over the world have similar dreams.



Yu, Calvin Kai-Ching. “Typical dreams experienced by Chinese people.” Dreaming 18.1 (2008): 1-10.

Nielsen, Tore A., et al. “The Typical Dreams of Canadian University Students.” Dreaming 13.4 (2003): 211-235.

Schredl, Michael, et al. “Typical dreams: stability and gender differences.” The Journal of psychology 138.6 (2004): 485-494.


Note: An earlier version of this article was first published on 3Quarksdaily.

Yu, C. (2008). Typical dreams experienced by Chinese people. Dreaming, 18 (1), 1-10 DOI: 10.1037/1053-0797.18.1.1
Nielsen, T., Zadra, A., Simard, V., Saucier, S., Stenstrom, P., Smith, C., & Kuiken, D. (2003). The Typical Dreams of Canadian University Students. Dreaming, 13 (4), 211-235 DOI: 10.1023/B:DREM.0000003144.40929.0b

Schredl M, Ciric P, Götz S, & Wittmann L (2004). Typical dreams: stability and gender differences. The Journal of psychology, 138 (6), 485-94 PMID: 15612605