Bryan Caplan's research on differences of opinion between expert economists and others finds (in his datasets) that there are big effects of education and IQ, bigger than liberal or conservative ideological effects, but the latter still remain: people with graduate degrees agree more with economists, but conservative PhDs in industry and liberal PhDs in academia tend to disagree with each other.

"a failure to grasp the empirical fact that personhood resides in brain structure: no neurons, no person."

Do you think that personhood is really an 'empirical fact'? How would you empirically measure when a developing fetus or infant's (or toddler's, depending on your view of personhood) brain becomes a person without a value-laden definition? Likewise for temporary or permanent brain damage.