By Ethan Zuckerman, on June 13th, 2011
Mathematical biologist Martin Nowak talks to us about the evolution of cooperation. Cooperation is a puzzle for biologists because it doesn’t make obvious evolutionary sense. In cooperation, the donor pays a cost and the recipient gets a benefit, as measured in terms of reproductive success. That reproduction can be either cultural or biological and the challenge to explain remains.
It may be simplest to consider this in mathematical terms. In game theory, the prisoner’s dilemma makes the problem clear to us. Given a set of outcomes where we’re individually better off defecting, it’s incredibly hard to understand how we get to a cooperative state, where we both benefit more. Biologists see the same problem, even removing rationality from the equation. If you let different populations compete, the defectors win out against the cooperators and eventually extinguish them. Again, it’s hard to understand why people cooperate.
There are five major mechanisms that biologists have proposed to explain the evolution of cooperation:
- kin selection
- direct reciprocity
- indirect reciprocity
- spatial selection
- group selection
Nowak works us through the middle three in some detail.
In direct reciprocity, I help you and you help me. This is what we see in the repeated prisoner’s dilemma. It’s no longer best to defect. As originally discovered by Robert Axelrod in a computerized tournament, the three-line program “Tit for Tat” wins:
At first, cooperate.
If you cooperate, continue to cooperate.
If you defect, defect.
While it’s a powerful strategy, it’s very unforgiving. If there’s a mistake, there’s an endless cycle of retaliation. Nowak wondered what would happen if natural selection designed a strategy. He created an environment to allow this, and permitting random errors to create a harder environment. If the other party plays randomly, the best strategy is to defect every time. But when tit for tat is introduced, it doesn’t last for long, but it does lead to rapid evolution. You’ll see “generous tit for tat” – if you cooperate, I will. If you defect, I will still cooperate with a certain probability. Nowak suggests that this is a good strategy for remaining married, and step towards the evolution of forgiveness.
In a natural selection system, you’ll eventually reach a state where everyone communicates, always. A biological trait needs to be under competition to remain – we can lose our ability to defect and become extremely susceptible to a situation where an always defect strategy can come into play. Cooperation is never stable, he tells us – it’s about how long you can hold onto it and how quickly you can rebuild it. Mathematically, direct reciprocity can come about if the benefits of cooperation, on average, outweigh the costs of playing a new round.
Indirect reciprocity is a bit more complex. The good Samaritan wasn’t thinking about direct repayment. Instead, he was thinking “if I help you, someone will help me.” This only happens when we have reputation. If A helps B, the reputation of A increases. The web is very good at reputation systems, but we’ve got simple offline systems as well. We use gossip to develop reputation systems. “For direct reciprocity, you need a face. And for indirect reciprocity, you need a name and the ability to talk about others.” In indirectly reciprocal systems, cooperation possible if the probability to know someone’s reputation exceeds the costs associated with cooperation. And this only works if the reputation system – the gossip – is conducted honestly.
In spatial selection, cooperation happens based on people who are close geographically, in terms of graph theory. Graph selection favors cooperation if there’s a few close neighbors – it’s much harder to do with lots of loose collaborators. A graph where you’re loosely connected to a lot of people equally doesn’t tend towards cooperation.
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By Winton Bates, on January 26th, 2011
   One of the benefits I have obtained from reading Nicholas Phillipson’s excellent book, ‘Adam Smith, an Enlightened Life’ is a better understanding of what Smith was trying to achieve in writing ‘The Theory of Moral Sentiments’ (TMS). He apparently saw the book as a contribution to a ‘science of man’ based on the observation of human nature and human history. As such, it provided a theory of sociability as well as a theory of ethics.
 Phillipson suggests that TMS can be viewed as a response to earlier writings of other scholars. In the interests of brevity, an appropriate place to begin the story is with David Hume’s view that human personality had been refined by the civilizing process – that humans were happiest when they were active and were best able to live an active life in a commercial society. By contrast, Jean Jacques Rousseau claimed that humans were naturally indolent and had only been truly at one with themselves in the ‘savage state’, before they discovered commerce and developed a vain desire for superiority over one another. Smith agreed with Hume – the TMS provides his view of how humans learn morality from the experience of common life and how this can lead to the improvement of society.
Smith acknowledged that everyone wants to better their condition. At one point he even seems to imply that everyone places higher priority on improving their relative position in society than on achieving an easier and more pleasurable life (TMS: 50). (My grandmother, whose life became easier and more pleasurable in the 1950s after she obtained her first refrigerator and washing machine, might have thought that comment to suggest that Smith was not sufficiently aware that he lived a privileged life. But I digress!)
Smith also makes the point that individuals should be responsible for looking after their own interests: ‘Every man is, no doubt, by nature, first and principally recommended to his own care; and as he is fitter to take care of himself than of any other person, it is fit and right that it should be so’ (TMS: 82). (I think Smith makes a stronger case for individual freedom here than who make the dubious claim that each individual is always the best judge of his or her own interests. But I digress again!)
Impartial spectators condemn violations of fair play among individuals competing to better themselves:
‘In the race for wealth, and honours and preferments, he may run as hard as he can, and strain every nerve and every muscle, in order to outstrip all his competitors. But if he should justle, or throw down any of them, the indulgence of the spectators is at an end. It is a violation of fair play that they cannot admit of’ (TMS: 83).
Smith’s ethics is based on the simple proposition that when individuals reflect upon their own past actions from the viewpoint of an impartial spectator they feel remorse when they have acted unjustly. His response to critics who suggested that he was reducing the principles of ethics to popular culture was that while children might seek to be universally agreeable, mature people who have important interests to manage find that they cannot please everyone. While some people might be content to follow popular culture, those who are morally responsible and fitted for public life have to establish their own impartial spectators as a judges in their own minds (Phillipson, p164-165).
 Irrespective of whether we find it useful to imagine an impartial spectator embodied within our selves, it is clear that humans do have the capacity to reflect on their own behaviour and to follow the dictates of conscience rather than always seeking immediate pleasure or following selfish interests. This is not always easy, however. As Jonathan Haidt points out, our efforts to become morally responsible may be hindered by our inner lawyers who seek to excuse us and blame others for our misdeeds. Haidt suggests that it is worthwhile acknowledging our faults to ourselves:
‘When you find a fault it will hurt, briefly, but if you keep going and acknowledge the fault, you are likely to be rewarded with a flash of pleasure that is mixed, oddly, with a hint of pride. It is the pleasure of taking responsibility for your own behaviour. It is the feeling of honor’ (‘The Happiness Hypothesis’, p79).
Identity economics, developed by George Akerlof and Rachel Kranton, may provide a useful framework to consider the process of character development that Adam Smith was discussing. Everyone obtains satisfaction from acting in accordance with their identity and is discomforted by acting contrary to it. A person who perceives himself or herself as the kind of person who respects the rights of others is likely to obtain satisfaction from acting in accordance with this ideal. This person may develop a reputation for trustworthiness and is likely to be trusted.
However, I don’t think it is particularly useful to try to think about development of identity and character outside the context of social interactions that reward particular behaviours and penalize others. It seems to me to be a fact of life that a person who identifies strongly as a member of a small community and has limited social interactions outside that community is less likely to feel conscience-stricken if he or she acts unjustly towards a stranger than towards another community member. The ethics of respect for the rights of strangers is no doubt encouraged to some extent by abstract ideals that would be endorsed by impartial spectators, but is likely to be more strongly encouraged by mutually beneficial commerce which offers ongoing rewards for ongoing cooperation between strangers.
By Winton Bates, on February 10th, 2010
In a post a few months ago I discussed whether Ayn Rand actually viewed selfishness as a virtue. I suggested that in arguing that selfishness is a virtue she was adopting a peculiar view of selfishness because the heroes of her novels did not seem to me to be particularly selfish.
The point was explained more clearly by Neera Badhwar in the recent discussion of Ayn Rand’s ethical thought on Cato Unbound (What’s living and dead in Ayn Rand’s moral and political thought):
‘Like Aristotle, Rand holds that the virtues, including justice, are not only means to the agent’s happiness, but also an essential, constitutive part of it. Julia Annas calls Aristotle’s ethical egoism a “formal” egoism because it essentially incorporates regard for others. Rand’s eudaimonistic egoism, likewise, is a formal egoism’.
Some other participants in the Cato discussion were not so sure that Rand viewed the virtues as an essential, constitutive part of the agent’s happiness.
Roderick Long noted that Rand appears to waver between treating virtue as a constitutive part of the agent’s own interest and as an instrumental strategy for attaining that interest: ‘The constitutive approach predominates in her novels: the chief reason that Rand’s fictional protagonists … do not cheat their customers, for example, is pretty clearly that they would regard such parasitism on the productive efforts of others as directly inconsistent with the nobility and independence of spirit that they cherish for themselves, and not because they’re hoping that a policy of honesty will maximize their chances of longevity’. He suggests, however, that in her philosophical writings that ‘her emphasis began to shift, though never unequivocally, to the instrumental reading’.
Other participants suggested that Michael Huemer had an instrumental reading of Rand’s views in mind in his initial contribution to the discussion. Huemer suggested that: ‘ethical egoism posits that the only thing that ought to matter intrinsically to me is my own welfare—for me, my own welfare or happiness is the only end in itself. It follows from this that I ought not to regard other individuals as ends in themselves; rather, I should see them only as means to my happiness—just as I see everything else in the world. This is a very simple and straightforward implication of the theory. I cannot hold my own well-being as the only end in itself, and simultaneously say that I recognize other persons as ends in themselves too’.
In defending the constitutive interpretation, Neera Badhwar made the point that ‘Rand shows her philosophy in the worlds she creates in her novels better than in her non-fictional statements’. I think this is a good point. Rand’s ongoing influence stems mainly from her novels rather than her philosophical writings.
Much of the Cato discussion centred on the question of whether what is good and right for one individual can ever conflict with what is objectively good and right for another individual. Douglas Rasmussen expressed his view that ‘if human flourishing is individualized and agent-relative … then this would mean that human flourishing is different for each person, and thus it is possible for there to be conflict—that is, there is no way that one can in principle rule this out’.
Roderick Long was closest to endorsing Rand’s view that there can be no conflicts between two people’s rational interests: ‘One’s individual nature can make the requirements of human nature more specific, but it cannot contradict them. …So the fact that the human good is individualized differently for different people doesn’t entail that one person’s good can conflict fundamentally with another’s.’
Neera Badhwar responded by suggesting that such fundamental conflicts, including situations where there are two equally good candidates for one job, occur frequently.
I think it is appropriate to give Douglas Rasmussen the final word in this highly selective summary of a complex discussion:
‘I do think that it is possible for people to cooperate peaceably. This is why basic negative rights are so important, but the issue here between me and Rand seems to be whether the existence of such rights depends on the assumption that what is objectively good for one individual cannot ever conflict with what is objectively good for another. I don’t assume this. She did.’
By Winton Bates, on April 27th, 2009
The essential feature of a tit-for-tat strategy is reciprocity – rewarding cooperation and punishing defection. In his book, “Born to be Good”, Dacher Keltner claims that “tit-for-tat instantiates the principle of cost-benefit reversal”. He argues that a set of mechanisms that reverse the cost-benefit analysis of giving is built into the human organism. He suggests: “These mechanisms might prioritize the gains of others over those of the self, and transform others’ gains into one’s own” (p. 71).
Keltner bases his claim that tit-for-tat involved cost-benefit reversal on three observations:
- When cooperation is the default setting, tit-for-tat favours mutually beneficial cooperation.
- Tit-for-tat is not envious – the strategy doesn’t change as a partner’s benefits mount.
- Tit-for-tat is a forgiving strategy – cooperation is resumed following the first cooperative action of a defector.
It seems to me, however, that none of these features of tit-for-tat necessarily involves prioritizing the gains of others over those of the self. It is possible for a tit-for-tat strategy to be adopted purely out of self interest. Robert Axelrod recognised this in “The Evolution of Cooperation” (p 173-4) , in his discussion of the experiments that Keltner uses as the basis for his discussion of tit-for-tat.
A tit-for-tat strategy based on self-interest provides a plausible explanation for the emergence of cooperation among strangers who have no reason to trust each other. For example, consider a situation where strangers are considering the initiation of trade in the absence of third party (e.g. government) protection against opportunistic use of force and fraud. From the perspective of each party the possible outcomes would be: a) a potential gain from trade; b) a potential loss resulting from opportunism by the other party – i.e. theft of the goods offered for trade; c) a potential gain from opportunism – theft of goods offered for trade by the other party; d) a stand-off.
If trade occurs in this situation, is it likely to be because one party places higher priority on the potential gains to the other party than on the potential gains to the self? I think it is more likely to occur because both parties consider that, in view of the likely responses of each other, they have more to gain from a series of mutually beneficial exchanges that they would gain from attempting to steal from each other.
If both parties adopt a consistent tit-for-tat strategy, then trade is likely to continue and they may come to trust each other. It is possible to envisage that the relationship could even develop to a point where they each gain some satisfaction from the benefit that they bestow upon each other through the exchange of goods. But this trust and affection is the outgrowth of mutually beneficial cooperation rather than a pre-condition for it.
I don’t understand why Dacher Keltner seeks to denigrate those who see self interest as a motivating force (see: How high was Adam Smith’s jen ratio?) and seeks to eliminate self-interest from the evolution of social cooperation. Perhaps he identifies the self-interest motive with opportunism, greed and selfishness to such an extent that he cannot see that it is good to desire to avoid being a burden on others, to help family members and other loved ones, and to accumulate the means to contribute generously to worthwhile causes. Perhaps he is uncomfortable with the idea that an invisible hand involved in voluntary exchange processes could enable people to benefit from cooperation with each other without actually intending to benefit each other.
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