Brain power improves by brain use, just as our bodily strength grows with exercise. And there is no doubt that a large proportion of the female population, from school days to late middle age, now have very complicated lives indeed.
In universities and intellectual circles, academics can guarantee themselves popularity - or, which is just as satisfying, unpopularity - by being opinionated rather than by being learned.
My belief has come about in large measure because of the lives and examples of people I have known - not the famous, not saints, but friends and relations who have lived, and faced death, in the light of the Resurrection story, or in the quiet acceptance that they have a future after they die.