The first ten [essays] appeared in The uniqueness of man ... and the last eleven in On living in a revolution."

The uniqueness of man.--Eugenics and society.--Climate and human history.--The size of living things.--The courtship of animals.--The intelligence of birds.--The analysis of fame.--Science, natural and social.--Religion as an objective problem.--Life can be worth living.--On living in a revolution.--Philosophy in a world at war.--War as a biological phenomenon.--Darwinism today.--Thomas Henry Huxley and Julian Huxley: an imaginary interview.--Dr. Spooner: the growth of a legend.--Birds and men on St. Kilda.--Tennessee revisited: the technique of democratic planning.--Colonies in a changing world.--"Race" in Europe.--Education as a social function.