Now, there is a division of opinion among American Catholics. Perhaps you noticed that I referred to conservative American Catholics. Those Catholics who dissent from the church's official teachings regarding sexual morality, including abortion in the first trimester, are at times referred to as dissenting Catholics or liberal Catholics. But liberal Catholics do not need to read Haidt to find out that conservative Catholics are fundamentalists, because they already know this. So apart from terminology about fundamentalists, what, if anything, would liberal Catholics learn from Haidt's book? Would liberal Catholics learn anything from Haidt's book that they could use to argue for new ways of thinking about Catholic moral doctrines? I doubt it.
For an informed attempt to reconstruct Catholic "natural law" moral theory regarding certain issues of sexual morality, see Todd A. Salzman and Michael G. Lawler's book THE SEXUAL PERSON: TOWARD A RENEWED CATHOLIC ANTHROPOLOGY (2008).
In short, Haidt's book seems to be aimed at a non-Catholic audience. But I hasten to add that there are other Christian traditions of moral reasoning. And there are Christians who see themselves as standing in their respective Christian traditions of moral reasoning. See, for example, Gary Dorrien's magisterial book SOCIAL ETHICS IN THE MAKING: INTERPRETING AN AMERICAN TRADITION (2011). But Haidt's book seems to be aimed primarily at people who do not see themselves as standing in an established Christian tradition of moral reasoning, Catholic or non-Catholic.
But this brings me to a far more troubling possibility regarding Haidt's book. For the sake of discussion, let us consider the possibility that Haidt does indeed know about the sweeping claim of the Catholic tradition of "natural law" moral theory -- the claim that Haidt himself sums up as claiming to be the "one true morality for all people, times, and places" (page 316). If he knows that the Roman Catholic Church teaches this, then he knows that he is writing against the Catholic Church, but he does not say that he is writing against the Catholic Church.
If we are to be concerned when anti-Semitic views are expressed, then shouldn't we be concerned when anti-Catholic views are expressed, especially when the author does not explicitly advert to the Catholic position?
But I have allowed that it is in the realm of the possible for someone to argue explicitly against certain Catholic teachings, as Garry Wills does and as Salzman and Lawler do. But to argue explicitly against certain Catholic teachings is argumentation. Pro-and-con debate involves thesis and antithesis. In the thesis/antithesis terminology that I am using here, Haidt is advocating the antithesis position from thesis position advanced by the Catholic Church. But in Haidt's way of writing without explicitly mentioning the Catholic tradition of "natural law" moral theory, the thesis position against which he is arguing remains a generalized thesis, not a thesis particularized to the Catholic Church. That is, he does not explicitly name the Catholic "natural law" moral theory as one example of the thesis position against which he is arguing. Nevertheless, Haidt's antithesis position is implicitly anti-Catholic. I see this as a problem. But I do not see explicit argument against the Catholic position as a problem, provided that the Catholic position is explicitly named as the real adversarial position against which one is arguing and fairly and accurately summarized.
Here are two recent books about anti-Catholic attitudes: Philip Jenkins' book THE NEW ANTI-CATHOLICISM: THE LAST ACCEPTABLE PREJUDICE (2003) and Mark S. Massa's book ANTI-CATHOLICISM IN AMERICA: THE LAST ACCEPTABLE PREJUDICE (2003).
Next, I want to turn to deontological moral theory. People of religious faith and people who have no religious faith could in principle embrace deontological moral theory. For the sake of discussion, let us suppose that people who have studied philosophy extensively and are committed to deontological moral theory were to read Haidt's book. Would reading Haidt's book lead them to give up their commitment to deontological moral theory, so that they would embrace Haidt's position instead? I doubt it.
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