Reply to Norian's "Evolution of the Rawlsian Ideal"

A week ago, Norian posted on the biologically evolutionary roots of the the cultural idea of social justice. Specifically, he discussed Rawls's conception of social justice, including the difference principle, which states that the most just society is that in which inequalities benefit the least well-off individuals. His write-up works well for even the condition of material adequacy held up (if discreetly) by libertarian thinkers like Rand and Hayek. Norian asks, "Why would anyone but the poorest in society advocate the welfare state?" At the end, he poses, "Is the most just system that which is most evolutionarily advantageous to its members?"

To answer Norian's closing question, we first have to define "evolutionarily advantageous." One definition is: "Facilitates an individual to produce more high-quality offspring than his/her peers."

Thinking about selection on the level of the individual, Norian's question appears a bit silly. By "its members," I assume he is referring to all citizens of a society. By definition, an evolutionarily advantageous society is one that loads the die in favor of some individuals over others. An "evolutionarily advantageous" society of 100 people cannot be advantageous for all 100. Therefore, it seems at first that no society, no matter how just, would be evolutionarily advantageous to all its members.

But Norian is a smart guy. As he hints in the last paragraph, he's probably looking to higher levels of selection (i.e. the group) when making his inquiry. Indeed, concepts of justice (such as Rawls's) emphasize society as a functional unit. Merely asking the question, "What makes a society just?" suggests that our minds have evolved in the context of selective pressures not just on the individual, but on the group as a unit. If this were the case, then our conception of a just society would be genetically tailored by a history of successful, tight-knit societies that out-competed others in reproductive terms. Consequently, a society functioning on that conception of justice would furnish that society with reproductive advantages over other societies. In this way, "the most just system" could be the "most evolutionarily advantageous."

In support of a group-selectionist argument, Norian writes (with the tip of his tongue in his cheek, I'm sure):

I know what you're thinking. No, if you're one of those people who hears the word 'group-selection' and laughs, you understand nothing about evolutionary biology. They're called different levels of selection, and yes, society exhibits heritability, variation and selection. The science that comes out in the next ten years is going to blow your mind.

Ok, so I don't laugh when I hear the word "group-selection," but in my mind I make the sound that you make when someone tells you a rather shocking bit of news while you're drinking a tall glass of chocolate milk. That's what I think most group-selection arguments are: delicious chocolate milk tragically gone down the trachea instead of the esophagus. It's a good idea, and Norian is right in saying that it can happen. The more vital question is, "Did it happen?"

I doubt that the differential success of ancient hunter-gatherer groups (as units) has much to do with our conception of justice. A lot of the results that one would expect from group selection can be wrought from selection on the individual in a group environment. Since humans are such social creatures, it makes sense that the enhanced (or diminished) reproductive fitness of an enterprising individual will naturally extend to humans of the same group through practices such as imitation. If a young genius invents the wheel, her whole society may benefit. That is not to say, though, that she invents the wheel "for the good of society" in any remote way.

Humans are cooperators. Good cooperators -- people who have entrusted their reproductive success in part to the actions of others -- have prevailed in the struggle for survival. Humans' adaptability is the reason why they have overrun the world.

My theory is that, by looking to improve the lot of its least well-off members, the most just society would be potentially evolutionarily advantageous at some hybrid level between individual and group. By lifting up the poor, a just society produces a group of more useful cooperators. In turn, individuals of all echelons stand to benefit over other individuals by cooperating more effectively than their peers. Through imitation and trade, these benefits come to all individuals, and the playing field starts to level out again. A just society is "evolutionarily advantageous" because it facilitates productive inequalities. These inequalities translate into reproductive benefits for certain individuals over others. The group is instrumental rather than an end unto itself.