The widely accepted heritability of IQ — between 57 percent and 80 percent in twin studies — is strong evidence for the materiality of the intellect.
A premise here is that abstract thought is a unique human endowment, so our colleague Wesley Smith will also find this of interest as a scientific test of human exceptionalism.
A reader asked whether this disproves the unity and freedom of the will. It appears that the patient wills two things simultaneously: getting dressed and getting undressed.
A scientific theory that on principle refuses to see the obvious is an achievement of which only humans are capable.
The failure to understand the gulf that separates humans from animals, and humans from machines, is a source of confusion to rival almost any other.