The course of human history is determined, not by what happens in the skies, but what takes place in our hearts.

Religious leaders and men of science have the same ideals; they want to understand and explain the universe of which they are part; they both earnestly desire to solve, if a solution be ever possible, that great riddle: Why are we here?

Whichever theory we adopt to give a rational explanation of human existence, that theory must take into account and explain the mental nature we see at work in all modern communities.

As long as man remains an inquiring animal, there can never be a complete unanimity in our fundamental beliefs. The more diverse our paths, the greater is likely to be the divergence of beliefs.

Human nature, as manifested in tribalism and nationalism, provides the momentum of the machinery of human evolution.

There are very few men and women in whom a Universalist feeling is altogether lacking; its prevalence suggests that it must be part of our inborn nature and have a place in Nature's scheme of evolution.

Man is by nature competitive, combative, ambitious, jealous, envious, and vengeful.