From: Bryan Douglas Caplan <bdcaplan at symbol phoenix dot Princeton.EDU> Subject:Game theory and evolution To: libernet-d at symbol Dartmouth dot EDU (Wed, 27 Oct 1993 14:08:15)
I’ve recently been reading a book called Demanding the Impossible: A History of Anarchism by Peter Marshall, and it has sparked a few thoughts on game theory, evolution, and their political ramifications.
Many people interpret Darwin’s theory of evolution as basically a Hobbesian theory. Everything is struggling to survive, and mercilessly crushes everything that stands in its path. Darwin’s view was not this simple, but he did delay the publication of the Origin of Species because he could not explain the suicidal behavior of bees who die when they sting to defend their hive.
If we put this over-simplified version of Darwin’s theory into the terms of game theory, we would say that always-defect is the evolutionarily strategic way to play the game. Applying the theory to human society, we would likely draw the same conclusions that Hobbes did: namely, a powerful state is necessary to check the destructive effects of the “evolutionary game.”
Now the 19th-century anarcho-communist Kropotkin wrote a critique of this interpretation of Darwin. The critique was called Mutual Aid; it argued that cooperation was a much more important factor in human evolution than conflict. Species that learned to cooperate would tend to survive much better than those stuck in perpetual conflict.
In terms of game theory, Kropotkin basically thought that we are evolutionarily programmed to play always-cooperate. He drew the political consequence that with the abolition of the state, our natural tendency to cooperate would re-appear and intensify. In consequence, everyone would happily take part in a order of voluntary communism.
The conclusions of socio-biology and modern game theory make an interesting contrast to both theories. Socio-biology explains Darwin’s bee-paradox thusly: the basic unit of evolution is not the individual but the gene. If one bee can save the lives of other bees WHO SHARE HIS GENES, he can promote his genes ever though he perishes himself. On this view, we have (as Kropotkin argued) an innate desire to help others; but in keeping with more standard evolutionary theory, this desire to help is limited to a fairly narrow group of other people who share our genes.
But what about the prevalence of cooperation not based on genetic ties? This is where modern game theory comes into play. Cooperation between people who share no genes couldn’t be based on universal altruism; otherwise, the all-defect strategy could always take advantage of the all-cooperate strategy. Rather, cooperation in the absence of genetic ties would have to be based on tit-for-tat, on reciprocation.
Strategically speaking, BOTH all-defect and all-cooperate encourage the other player to play all-defect. But tit-for-tat, in contrast, encourages other players to play tit-for-tat. This makes it an evolutionarily dominant strategy, since it makes cooperation correspond to narrow self-interest.
Now I think that this evolution/game theory has interesting political implications as well. It tends to argue that, unlike the (oversimplified) Darwinian theory, a powerful state is not necessary to create cooperation. But it also argues against Kropotkin’s theory that voluntary communism could work well, since his system is based on universal altruism rather than on reciprocation. Instead, the third theory tends to support libertarianism, since it shows how cooperation can arise without the state, but only if the system preserves individual incentives and individual responsibility. Evolution does promote cooperation, but only cooperation based on reciprocation, not unilateral giving.
According to David Graeber, there is a general “baseline communism” in social relations in that we do (and sometimes trade) many things without expecting anything in return: a light/match, a bite of food, fixing a flat, reaching an item or opening a jar for someone, holding the door…the list can go on for pages I imagine. He says this baseline communism is the glue of society, a general sense of interdependence, and what seems to me to be “care.” To this end I have to add that empathy (or even love) may be a form of communism as well in that we are giving something people often need (or crave) for ‘free’– the recipient gets paid in endorphins or oxytocin. There are situations of course where people pay for “love,” and/or sex.
The relationship many people have with their pets is primarily one of love, quite often though its the pet that’s unconditional. Pets certainly come to mind in these “communist” situations.
In addition to the baseline communism, there are people we often have tighter bonds with, where it is often a “one-to-one” case of the communist mantra “from each according to their ability, and to each according to their needs.” To Graeber, this is a case of “individualistic-communism” that we often cannot refuse or turn away from. It didn’t jump off the page (Debt:The First 5,000 Years) at me as to why/how this was individualistic-communism, but I imagine its that the one-to-one interaction is fulfilling individual needs based on abilities without expecting reciprocity/trade. There is ‘reciprocity in the broad sense’ in that giving gifts or a hand is often seen as a gesture where the giver feels the receiver ‘would do the same for me,’ “not necessarily that they will.” I think in some situations this is true.
According to Marcel Mauss, gift giving can make the receiver feel obligated to reciprocate, and/or the giver has an advantage. The only “survival” situation that comes to my mind is in times of great need. Suppose the giver runs out of food, and the receiver has some to share and knows the giver is in need, then the tables turn until the next similar episode.
As Caplan pointed out above, there are situations where relationships between organisms increase the “fitness” of individual A or group A, but occur at a cost to individual B. Caplan essentially alluded to “biological altruism,” as well as Hamilton’s rule: c<b*r: the (c)ost to the altruist is less than the (b)enefit to the recipient multiplied by the coefficient of (r)elatedness. Closer genetic relatedness increases altruism and fitness, it decreases towards more distant kin.
In ecology, there are four relationships that come to mind:
- commensalism– one organism benefits and the other does not benefit +/0
- mutualism– both organisms benefit +/+
- parasitism– one organism benefits and the other pays +/-
- altruism– which can be framed as any of the proceeding three, but usually as a type of parasitism +/-
The first two represent “cooperation,” and altruism is often seen as ‘charity.’ Like many ethical-type premises, how altruism is framed may change how its justified or explained.
Joan Roughgarden lays out ‘social selection‘ in Genial Gene. It seems to be mutualistic cooperation for biological success. It’s interesting to consider the “moral molecule” (oxytocin) as behind some of our interactions, and whether it might explain social selection.
Do we need to explain everything based on biological success? Is it appropriate to frame some of this from an egoist pov where doing good makes you feel good, and this alone explains (some) interactions? Are selfishness and individuality a snap-shot like marginal-theory, whereas social selection theory is the long-run big picture like labor-theory, both complementary and inseparable? Do these questions or the question of altruism’s evolution (or existence) even need to be answered? Can they be answered?
I will stop here, but plan to continue to build on these thoughts.