Tag Archives: altruism

The Evolution of Cooperation: Thankfulness and Inspiration as Two Routes

Cooperation or Altruism or Prosociality is the tendency to help others, even at a cost to oneself. Naive conceptions of evolution, make us think that cooperation or altruism cannot evolve because the genes are selfish and only care about perpetuating themselves. However, the selfish gene view of evolution does not preclude organisms to become altruistic if for example they share genes ; one of the mechanisms for the same is kin selection.  

Another mechanism that can give rise to cooperation is direct reciprocal altruism. In colloquial language, it is akin to you scratch my back and I’ll scratch yours.  You help someone in their time of need and expect that the person will help you back in your time of need. Consider our hunter/ gatherer ancestors; if one of them made a big kill and shared with a con-specific, it becomes more likely that the peer will share with him when good fortune shines on the peer.

A necessary condition for reciprocal altruism to evolve is the ability to punish if someone doesn’t reciprocate or at least to not keep trusting that freeloader in future. Both punishment as well as not indulging with that person again or repaying a past benefactor, depends on the ability to remember the person whom who we have helped or who has helped us. This ability will typically involve remembering faces. Another ability that will come handy is the ability to gauge intentions- whether the person who helped did it on purpose or accidentally.

Yet another mechanism that gives rise to cooperation is indirect reciprocity. I help you and you help someone else. While in direct reciprocity, a pair or dyad helps each other over time or helps now with the hope/ expectation of a payoff in the future; in indirect reciprocity, one helps a stranger just because one has been helped by someone. Indirect reciprocity works by creating a culture of altruism, where helping becomes the norm and people accumulate reputations.

Now, direct reciprocity can work by encouraging feelings of gratitude in a beneficiary. These feelings of thankfulness and indebtedness towards the benefactor , act together to ensure that the person receiving favors, returns them.

Indirect reciprocity works similarly, by promoting feelings of elevation or inspiration in the general public who may be recipient or even just witnessing a virtuous act of kindness, morality etc. . Once such feelings are aroused, the person witnessing such acts become more likely to act prosocially.

The above may seem speculative, but there is solid evidence around the evolution of direct reciprocity as well as indirect reciprocity. and so too is there strong linkage between direct reciprocity and gratitude. The link between indirect reciprocity and elevation is also hinted.

For example, consider the following article by Sui et al that shows that trait gratitude and trait elevation have different neural correlates. From the abstract:

We demonstrated that trait gratitude was positively correlated with gray matter volume (GMV) in the left cerebellum extending to fusiform gyrus, and also the right middle occipital gyrus (MOG) extending to posterior superior temporal sulcus (pSTS) and temporoparietal junction (TPJ), while trait elevation was negatively correlated with GMV in the left dorsolateral prefrontal cortex. While controlling each other, all the regions still held significant, except the right MOG and pSTS/TPJ. The results indicate that there are distinct neuroanatomical correlates for proneness to gratitude and elevation, while the evidence is mixed that pSTS/TPJ may be the common correlates for them.

The authors discuss the implications of above: gratitude  is associated with more GMV in fusiform gyrus, an area important for remembering faces, and is thus the emotion associated with direct reciprocity where remembering faces is important. Also, both gratitude/ elevation are associated with  pSTS and TPJ, areas important for attributing and inferring intentions to others. Elevation further is negatively associated with GMV  in left DLPFC, a region that involves thinking in a utilitarian manner rather than in intuitive manner about moral issues. As per dual process theories of morality one can either take a intuitive, de-ontological stand where a moral act is moral because it is the right thing to do or a duty to uphold; or the second pathway consists of more deliberate, utilitarian reasoning whereby one looks at acting such that happiness/utility is maximized for maximum number of people. Trolley problems are famous examples of such utilitarian reasoning battling with moral intuitions. 

 To me the differential neural correlates of gratitude and elevation, as well their different manifestations at the emotion and behavioral level, strongly suggest that they are associated with different types of altruism- direct and indirect respectively.  

The Evolution of Altruism And Its Relationship to Personality

Altruism, put simply, is helping others or cooperating with others, even if it is costly to self. Of course, something like that cannot evolve, unless there are benefits too, associated with such acts of apparent selflessness.

Evolutionary theory mandates that there be some genetic payoffs in terms of either inclusive fitness or future benefits to self (reciprocity) for any kind of altruism/ cooperation to evolve.

I recommend reading Wikipedia articles on reciprocity, kin selection, and evolution of cooperation if they are not familiar to you or you need a refresher.

Cooperation, to start with, can evolve based on three forms of reciprocity: direct, indirect and network. All are based on the fact that there re repeated interactions between group of people- dyads, triads or many more. Reciprocity can typically be measured in the lab using the repeated Dictator/ Trust game.

Direct reciprocity was proposed by Robert Trivers as a mechanism for the evolution of cooperation. If there are repeated encounters between the same two players in an evolutionary game in which each of them can choose either to “cooperate” or “defect”, then a strategy of mutual cooperation may be favoured even if it pays each player, in the short term, to defect when the other cooperates.

Here, in direct reciprocity A trusts/helps B and hopes that when time comes B will reciprocate/help A. The top-of-the-mind factor is whether or not to trust somebody and whether or not to reciprocate someone’s trust. Trust and exploitation may be relevant issues here. In the Dictator/ Trust game this trust/exploitation manifests as the amount that is split and given to the other person vs kept with oneself.

In the standard framework of indirect reciprocity, there are randomly chosen pairwise encounters between members of a population; the same two individuals need not meet again. One individual acts as donor, the other as recipient. The donor can decide whether or not to cooperate. The interaction is observed by a subset of the population who might inform others. Reputation allows evolution of cooperation by indirect reciprocity.

This is partially correct that reputation for being trustworthy helps in indirect reciprocity; however that is only true for the downstream version; for the upstream version feelings of gratitude/happiness/awe/elevation in persons receiving the help/ witnessing the act also lead to more pro-social behavior by those receiving help/ witnessing. Thus feelings of gratitude/ awe/elevation mediate this kind of upstream indirect reciprocity. See below for upstream and downstream variants.

Individual acts of indirect reciprocity may be classified as “upstream” or “downstream”:

  • Upstream reciprocity occurs when an act of altruism causes the recipient to perform a later act of altruism in the benefit of a third party. In other words: A helps B, which then motivates B to help C.

  • Downstream reciprocity occurs when the performer of an act of altruism is more likely to be the recipient of a later act of altruism. In other words: A helps B, making it more likely that C will later help A.

Before touching upon network reciprocity, I will take a quick detour about kin selection. I believe kin selection or inclusive fitness is also a type of reciprocity (that between related individuals sharing genes) and may be rechristened genetic reciprocity. After all if A is likely to help B because they share x % of genes, the reverse is equally true and applicable. And of course this is mediated by emotional attachment to the kid/kin.

As per one definition of kin selection:

A biological theory stating that a gene that causes an organism to exhibit behavior detrimental to its survival will increase in frequency in a population if that behavior benefits the organism’s relatives, which will pass the gene on to subsequent generations.

If I slightly change words form above definition, I can now define a neighbor selection process as a cultural theory stating that a meme that causes an organism to exhibit behavior detrimental to its survival will increase in frequency in a population if that behavior benefits the organism’s neighbors, which will pass the meme on to subsequent neighbors.

We are now ready to look at network reciprocity:

Real populations are not well mixed, but have spatial structures or social networks which imply that some individuals interact more often than others. One approach of capturing this effect is evolutionary graph theory, in which individuals occupy the vertices of a graph. The edges determine who interacts with whom. If a cooperator pays a cost, c, for each neighbor to receive a benefit, b, and defectors have no costs, and their neighbors receive no benefits, network reciprocity can favor cooperation.

Basically, what I understand from the above is that if you help your neighbors sometimes such that the cost is not too high but benefits to neighbors are high and if  cost to benefit compares favorably with average number of neighbors/ neighborly interactions you have, then in the long run you will benefit and this form of cooperation can evolve.  To me the effects are mediated by the number of neighbors or sociability of a person.

Of course, even if you have all these mechanisms in place, cooperation may not evolve, as you may have free-riders. One important mechanism that has evolved to keep the free-riders in check is that of punishment. And once punishment is part of the picture you don’t even need repeated interactions, one-off games may be sufficient. I call this phenomenon Direct Punishment. One way it has been measured is with the Ultimatum game.

In the Ultimatum game, the second player can inflict costly punishment on first player by refusing to accept the division; this costly punishment is dyadic in nature and the aggression/hostility/vengefulness of the second player ensures that cooperation in even one-off encounters happens.

Basically instead of trusting and helping B, A starts by exploiting B and B retaliates by punishing A at cost to oneself.

Of course one can then surmise that there can be a phenomena of indirect punishment. This again may happen in two ways:

  1. Indirect punishment upstream: A is exploitative in nature; A exploits B; B punishes A, who then feels guilt/ gets reformed and stops exploiting C or even starts helping C.
  2. Indirect punishment downstream: A is exploitative in nature: A exploits B, B punishes A; B gets a reputation for being tough/competent and stops getting exploited by others say C or C may now even help B.

The Indirect reciprocity effects can be seen in Public goods/ trust game.

I will now take a detour and introduce the HEXACO model of personality which set me thinking about this in the first place.

HEXACO is an alternate personality model that is based on the same principles as the Big Five/FFM; i.e. it uses factor analysis of lexical terms in various languages to arrive at major personality traits.

The six factors are generally named Honesty-Humility (H), Emotionality (E), Extraversion (X), Agreeableness (A), Conscientiousness (C), and Openness to Experience (O). The personality-descriptive adjectives that typically belong to these six groups are as follows:

  • Honesty-Humility (H): sincere, honest, faithful, loyal, modest/unassuming versus sly, deceitful, greedy, pretentious, hypocritical, boastful, pompous

  • Emotionality (E): emotional, oversensitive, sentimental, fearful, anxious, vulnerable versus brave, tough, independent, self-assured, stable

  • Extraversion (X): outgoing, lively, extraverted, sociable, talkative, cheerful, active versus shy, passive, withdrawn, introverted, quiet, reserved

  • Agreeableness (A): patient, tolerant, peaceful, mild, agreeable, lenient, gentle versus ill-tempered, quarrelsome, stubborn, choleric

  • Conscientiousness (C): organized, disciplined, diligent, careful, thorough, precise versus sloppy, negligent, reckless, lazy, irresponsible, absent-minded

  • Openness to Experience (O): intellectual, creative, unconventional, innovative, ironic versus shallow, unimaginative, conventional

The factor H is a new factor not present in Big Five/FFM. The E though looking similar to N of big Five, is conceptually different; it no longer contains anger/hostility which are instead present in HEXACO A. similalrly there are important differences between HEXACO A and Big Five A. the other 3, C, O and X (extarversion) are similarly conceptualized and defined in both systems and have same loadings when tested together.

Ashton and Lee, the proponents of the HEXACO model, have themselves related evolution of altruism to these traits [pdf] and I am building on their work.

Basically as per them,

To begin, we have proposed that the Honesty- Humility and Agreeableness factors represent two complementary aspects of the construct of reciprocal altruism (Trivers, 1971). Honesty-Humility represents the tendency to be fair and genuine in dealing with others, in the sense of cooperating with others even when one might exploit them without suffering retaliation. Agreeableness represents the tendency to be forgiving and tolerant of others, in the sense of cooperating with others even when one might be suffering exploitation by them. (For a discussion of two broadly similar, although not identical, constructs, see Perugini, Gallucci, Presaghi, & Ercolani, 2003.) Presumably, high levels of Honesty- Humility are associated with decreased opportunities for personal gains from the exploitation of others but also with decreased risks of losses from withdrawal of cooperation by others. In a similar manner, high levels of Agreeableness are associated with increased opportunities for personal gains from long-run reciprocal cooperation with others, as well as with increased risks of losses from exploitation by others. (Note that we use the term altruism in terms of a dimension of altruistic versus antagonistic tendency, which involves both a willingness to help or provide benefits to others and an unwillingness to harm or impose costs on others.)
In addition, we have proposed that Emotionality represents tendencies relevant to the construct of kin altruism (Hamilton, 1964), including not only empathic concern and emotional attachment toward close others (who tend to be one’s kin) but also the harm-avoidant and help-seeking behaviors that are associated with investment in kin (see also Lee & Ashton, 2004). Presumably, high levels of Emotionality are associated with increased likelihood of personal and kin survival, as well as with decreased opportunities for gains that are often associated with risks to personal and kin survival.
To me, this looks like equating direct reciprocity with H and direct punishment with A.  With this in mind I now list the personality trait (HEXACO)/ evolution of altruism linkages.
1. Kin Selection/ Genetic Reciprocity : mediated by emotional attachments etc and related to Emotioanlity.
2. Neighbor Selection / Network Reciprocity: mediated by sociability and related to sociability aspects of Extrarversion.
3. Direct Reciprocity : mediated by trusting others and being honest and related to Honesty-humility.
4. Direct Punishment:  mediated by punishing others and being aggressive/ hostile when needed and related to Agreeablness.
5. Indirect Reciprocity upstream:  mediated by feelings of gratitude/ awe/ elevation and possibly related to Openness to Experience
6. Indirect Punishment upstream: mediated by feelings of guilt/responsibility and related to Conscientiousness.
 7. Indirect Reciprocity downstream: mediated by signaling and being trustworthy; need a new personality dimension for this.
8. Indirect Punishment downstream: mediated by signaling and being competent/ tough and possibly related to Surgency dimension of Extarversion.
I am more and more convinced, looking at the above model that we evolved to be cooperative/ altruistic rather than otherwise.

Altruism as a result of sexual selection

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There is a new article in BPS, that has found some evidence for the fact that altruism may have evolved by the process of sexual selection.

There are many mechanisms that underlie exactly how and why sexual selection takes place- one is the ‘handicap’ /’costly honest signal‘ theory according to which a trait that is actually disadvantageous or a handicap for the host evolves to signal exactly that fact- that despite this handicap I am able to function well and must therefore be of better genetic quality; the most common example being the evolution of peacocks tail which is a handicap and makes the male peacock carrying a big tail more vulnerable for predation, but also is attractive to females and preferred by them.  Another theory is that of ‘runaway selection’ i.e . a trait may evolve in a direction due to some genetic drift and the preference for it may also evolve in tandem such that there is  a slight leaning or preference towards that trait. Now, in a competition, those, typically males, who have that trait will be selected by the females and their progeny will have an advantage as they are more likely to display that trait and be favored by subsequent generations; thus an arbitrary trait may get fixed by this runaway selection where all members of the species want to be part of the new fashion/club in town. I know I am drawing very loose analogy, but just to give an idea. Nakedness or loss of hairs in humans is predicted to have followed this pattern.

Of course sexual selection also differs on whether it is largely intrasexual, driven by competition (selection pressure) between males for eg  having big antlers to defeat and subjugate another male; or is driven by mate preferences and has intersexual selection dynamics- like the peacocks tail.

What the authors of this paper hypothesized was that sexual selection is behind the evolution of altruism or selfless concern with non-kin and that this being the case and this sexual selection dynamics being driven by inetrsexual dynamics, there are bound to be genetic underpinnings to both the trait altruism as measured in males/females and the mate preferences for altruistic trait in both females as well as males. The reason they didn’t anticipate any differences in male sand females was that parental investment, as per them, is roughly equal in case of humans and so both males and females exert equally strong sexual selection pressure son each others traits and ‘choose’ their mates equally.

However, in this study they looked only at females and their genetic basis for altruistic traits as well as mate preference for altruism. The altruistic traits and mate preferential weer measured using self-report instruments.  the genetic components underlying these were estimated using classical twin studies paradigm where correlation between mono-zygotic twins and di-zygotic twins are compared to estimate the genetic contribution. They also calculated the phenotypic correlation between mate preference for altruism and altruistic trait in individuals and tried to calculate how much of this correlation again was genetic in nature or in other words was a result of  mating between those who had the trait and those who preferred the trait. . They hypothesized that in the ancestral environmental this type of mating for trait altruism would have taken place and thus these would be genetically correlated.

This is exactly what they found; they found that both altruistic personality and mate preference for altruism had genetic components and that they both co-varied and that covariance again had genetic component.  the pare itself is full text open access and is written very well, so go ahead and read it yourself. this is an important paper that has come timely when the whole kin-selection paradigm for evolution of eusociallity is being challenged by E o Wilson and team and provides a fresh and alternative perspective of why altruism may have evolved.

Here is a tit-bit from the discussion:

We believe that the sexual selection hypothesis for the evolution of human altruistic traits should now be considered alongside other more established theory (Bshary & Bergmu¨ller, 2008; Lehmann & Keller, 2006), particularly as there is the possibility that multiple mechanisms might underlie a complex behaviour such as altruism. Empirical testing of contrasting theories might even be possible. For example, reciprocal altruism (Trivers, 1971) does not strictly predict the genetic correlation between MPAT and ‘altruistic personality’ found here as ongoing reciprocation towards others would not necessarily result in such a selective process. Indirect reciprocity (Leimar & Hammerstein, 2001) concerns reputation directed towards all other group members while the sexual selection hypothesis focuses solely on altruistic displays that can be evaluated by potential mates (Phillips et al., 2008). A study that examined ‘costly signalling’ of altruistic behaviour through personal donation to a children’s charity found a significant effect on male behaviour when witnessed by a female observer while no such effect was found when male participants were observed by same sex others (Iredale et al., 2008), a finding that could be seen to be at odds with indirect reciprocity. Additional studies could further elucidate the effects of altruistic reputation when directed towards same sex others as opposed to potential mates, thus testing the relative claims of indirect reciprocity against the sexual selection hypothesis.

Tim Phillips1, Eamonn Ferguson2, & Fruhling Rijsdijk (2010). A link between altruism and sexual selection: Genetic influence on altruistic behaviour and mate preference towards it British Journal of Psychology DOI: 10.1348/000712610X493494

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Am happy, will be selfish; Am sad, will be fair. Oh Really?!?

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Many a times, researchers have their own personal agendas and its very human to fall in to the temptation to interpret study results or spin them to suit ones long term subject matter and expertise.  This is a trap in which Joe Forgas et al fall when they report in JESP that happy people are selfish and sad people are fair. They have a long research interest that goes aka sadness is beneficial for you and every result has to fit in that model.

In this latest study they use the behavior in the dictator game as a proxy for selfish behavior. the classical dictator game consist of giving a  sum of money to a person and asking them to divide it between themselves and another human being any way they deem fit. If an agent is rational , he should be purely selfish (there are assumed to be no future/past interactions and no reputations to maintain/ cultivate) . As is the normal finding, humans normally give upto 50 % of their share to another person in the dictator game although there are no obligations. As such , dictator game is indeed a good measure of internal selfishness of a person.

What Joe et al do is to induce good(happy)/bad(sad) mood  in their subjects and then ask them to play a version of the dictator game.  So far so good. However in their version of the dictator game , one is not given a sum of money to divide amongst oneself and someone else; but they are given 10 raffle tickets- each raffle ticket increasing the odds of winning a lottery of 20 $. Now ,here is where I think they have blundered an confounded the results. they have introduced odds and probability thinking in the scene and everyone knows that a normal person prefers a sure sum of money (10 $) over a chance of winning equivalent sum  (50 % chance of 0$ and 50  % chance of 20 $). Both utilities are mathematically equivalent but we are all normally risk-averse and prefer the assured sum. However, and this a big however, happy people are more risk prone and may prefer a chance much more than an assured sum. In sad mood things would be reverse.

Its not as if Joe et al are not aware of the happiness-risk proneness link, but they somehow ignore it and let it confound the results. To quote form the paper:

Happy mood may also function as a motivational resource (Trope, Ferguson, & Raghunanthan, 2001), allowing happy individuals to accept greater risks. These findings suggest that happy mood should promote a more confident, selfish allocation strategy, while negative mood should trigger more cautious, fair allocation.

Readers will immediately see where I am coming from. I am a huge fan of seeing happiness/ sadness in terms of environmental risk and safety and as motivational focus- promotion versus prevention focus. It is thus pretty obvious to me that a (or say 10) raffle ticket (a chance of winning 20 $) does not have the same value for a sad person a sit has for a happy person who is more in a risk -prone frame of mind. thus, it seems obvious that a happy person will adhere more utility to the raffle tickets and may not that readily part with them; while a person in a sad mood may think that chancy bit of paper as worthless and be more willing to share it with others. I challenge Joe et al to repeat the experiment with real money and not waffle tickets and then draw any conclusions.

Whats more in the first experiment (described above) the selfish tag on happy people was due to the fact that they did not share that much with out-groups. If out-groups (strangers ) were not present perhaps the results would not have been significant based on ingroup data alone. If, somehow, being sad broadens your vistas and makes you treat outgroups (strangers) the same as ingroups, then this would again confound the result and invalidate the conclusions reached by the authors. Of course this thesis that being sad ,makes you more open to strangers flies in face of the study I covered yesterday that sad people prefer familiarity;  but it is something to think about and design experiments to rule out.

Experiment 2 suffers from the same methodical flows. Experiment 3 tried to prove that when social expectations about being fair were relaxed, then happy people gave free rein to their selfishness and became selfish, while sad people remained fair and followed external norms of fairness. This is purportedly to relate it to the internal focus of selfish people and external focus of sad people and fit in a larger framework, but again it fails to convince me. At the outset let me clarify that I do adhere to happy people have internal focus while sad people are more driven by external norms. However the experiment they did supports my thesis sand not theirs.

In experiment 3, they manipulated the perceived social norm of fairness by revealing to subjects the behaviour of some hypothetical earlier participants in the dictator game. some were in the ‘fairness is the norm’ condition (more fair splits be earlier hypothetical participants), others were in the ‘fairness is not the norm’ condition- I like to call this ‘unfairness is the norm’ condition.

Now there are two caveats to this. First not everyone decides whether to act fairly or not based on existing norms. As per Kohlebrg’s or other modern developmental theories one sense of morality in an earlier stage may be driven by norms , but at later stages is determined by internal values and internalized norms. thus it is wrong to apriori believe that if people don’t act selfish it is because of pressure of the social norm of fairness. This is the position that study authors take and this is not necessarily true. Second, even if one grants that one works under social norms, it is false to believe that the social norm is fairness;  with the myriad misinterpretations of darwins theory selfishness has become the de facto social norm. Thus, one can as legitimately claim that selfishness is the existing norm that goes undermined by manipulations of experiment 3 and when primed with fair prior dictator behavior, gives free rein to mood effects to take place; while in the second condition where selfishness norm is reaffirmed there are no mood effects.

This hair splitting is important because in the third experiment they did not find a main effect of mood/ prior fairness norm  on dictator offerings, rather there was an interaction between the mood and prior priming. They found that when prior exposed to social norm of fairness there was no difference in happy and sad condition; the difference was there only in ‘selfishness is norm’ condition. One can thus, also interpret these findings as ‘selfishness is norm’ – in that selfishness norm when chances are involved happy people make more risky choices than sad people; however when the norm of selfishness is undermined, internal values like being fair (yes there is considerable literature that being fair is more natural and internally driven than being selfish)  takes hold and make seven happy people who value the raffle tickets a lot to become more fair and altruistic and share their tickets to the same extent as sad people do normally.

Its not as if they haven’t considered the dilemma of why the norm and undermining of it should be one way only. To quote:

Why did sad people not simply follow the norm – fairness or selfishness – and happy people follow their own internal state (i.e., ignore the norm and act selfishly) in this study? It is likely that information provided about the selfish behavior of others, being socially undesirable, could not invoke an acceptable, alternative shared social norm, and so served merely to undermine the powerful norm of fairness, allowing full scope for mood effects to occur. In contrast, information about the socially desirable, fair behavior by others served to reinforce a powerful existing social norm and so constrained mood effects, as found here.

So in summation, I am not convinced, I still believe the results they got are due to the happiness as increasing risk proneness effct. But I agree broadly with their thesis that sadness also has adaptive value and happiness should not be seen as all rosy and sadness all bad. The bad effect of extremes of euphoria/ mania are well known, to complement lets hear what they have to say of the good effect of sadness. I’ll like to end with their own quotes on this matter.

Interestingly, our results further challenge the common assumption in much of applied, organisational, clinical and health psychology that positive affect has universally desirable social consequences. Together with other recent experimental studies, our findings confirm that negative affect often produces adaptive and more socially sensitive outcomes. For example, negative moods can improve the detection of deception (Forgas & East, 2008), reduce judgmental errors (Forgas, 1998), improve eyewitness accuracy (Forgas, Vargas, & Laham, 2005), and improve interpersonal communication strategies (Forgas, 2007). The present experiments confirm this pattern by demonstrating that mild negative moods also increase fairness and sensitivity to the needs of others.

Tan, H., & Forgas, J. (2010). When happiness makes us selfish, but sadness makes us fair: Affective influences on interpersonal strategies in the dictator game Journal of Experimental Social Psychology DOI: 10.1016/j.jesp.2010.01.007

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