Take the following statement:
In defense of Jason Richwine and Charles Murray
Ordinary people understand that it is irrational to discriminate according to race or religion or ethnic group, and that it is rational to judge individuals on their own merits.
And then attempt to answer the question.
One sense of “rationality’ is that employed in discussions of economic theory. Let us call this: “economic rationality”. By this sense, “rational” means maximizing one’s good, where “maximizing” means “most efficiently pursuing”.
Racial discrimination would be rational in this sense insofar as it maximizes one’s end. If one’s end was, say, a racially homogenous or heterogeneous i.e., “diverse” institution, then discriminating on the basis of race would be rational. Conversely, given the same end, it would be irrational to discriminate on the basis of weak proxies.
Given this, what Barone must mean is that “race or religion or ethnicity” is not a part of the good of “ordinary people” — or he must be using “rational” in some queer non economic sense.
Now, let us conjecture that by the understanding of so called “ordinary people” racial or religious or ethnic homogeneity/heterogeneity is, indeed, not an end. What would this establish? Nothing. Any direct extension beyond this would represent an argumentum ad populum.
I suspect that Barone recognizes this. Thus I suspect that he is using “rational” in some queer sense — that he means that the valuing of racial or religious or ethnic homogeneity/heterogeneity is not something that sane people do.
Now, I find that to be a curious prejudice — especially in light of the previous discussion.