Hauser argues that we have an innate moral faculty. Like the language instinct of Chomsky, a moral “organ” is built into our biology. Evidence for this he states is seen cross-culturally, in a universal propensity for fairness and reciprocity, and within young infants. As to what this moral faculty is, Hauser contrasts his favored Rawlsian position with Hume’s emotions and Kant’s pure logic, yet draws lessons from each. From Rawls, Hauser states that moral principles are innate and unconscious. We judge for fairness (strict equality) with empathetic support (a “rational benevolence”) for those who are more in need (i.e., these are Rawls’ two principles of justice).
I don’t believe this account of our “moral faculty" is accurate. Rawls speaks of our freedom -- the innate need to move unimpeded and, thereby, to do what is necessary to survive and promote our well being –- and the need to restrict that freedom when it impedes the freedom of others to do the same. While there's a moral logic involved here (that we must respect the freedom of others if we are to enjoy our own freedom), others see an opposing logic that says they do not have to restrict their freedom out of deference to others if they are able to manipulate, deceive (ironically, operating under a “veil of ignorance”). Both approaches work in terms of evolutionary survival and this might explain what we see throughout our history – the twin poles of behavior and everything in between.
The description above is, in a sense, a utilitarian calculus, with some opting for fairness and others opting for more self-oriented actions. The former approach is buttressed in many individuals by the innate sense of fairness and benevolence that Hauser states is Rawls’ position. But rather than making this a universal characteristic of human nature, it could be a subset that applies to some individuals more than others, though even this sense of fairness and benevolence may not extend to humanity as such but only to our “tribe.”
Hauser extensively cites this study and that study and it’s easy to get lost and overwhelmed and to lose the main current of his argument. I also believe he misreads Piaget. After making a gratuitous comment (if Piaget had “only read Aristotle”), Hauser states that Piaget failed to explain how children move through the stages of moral development. Piaget it seems to me is clear enough on that point. As the child develops, physically, it is also encountering the “shocks and opposition” (Piaget’s words) from the world that force the child to progressively de-center and to view itself necessarily as part of a larger environment that it must accommodate. Ultimately, and theoretically, this ends in the abstract fourth stage where a young adult has the capacity to transcend the here and now and think in universal, moral terms (i.e., a Kantian like hypothetical imperative – that states that it is in one’s interest to respect the other as an end; or a golden-rule type principle in all of its variations). However, this presupposes a motivation to want to follow such a standard. If that motivation is absent, the standard means nothing. Hauser presumes that such a motivation is universal (from the “moral organ” or “moral faculty”), but it is more likely that humans vary in their predominant, overall motivation between the twin poles of egocentrism and other-regarding behavior.