Some things mankind can finish and be done with, but not ... science, that persists, and changes from ancient Chaldeans studying the stars to a new telescope with a 200-inch reflector and beyond; not religion, that persists, and changes from old credulities and world views to new thoughts of God and larger apprehensions of his meaning.

We ask the leaf, "Are you complete in yourself?" And the leaf answers, "No, my life is in the branches." We ask the branch, and the branch answers, "No my life is in the root." We ask the root, and it answers, "No my life is in the trunk and the branches and the leaves. Keep the branches stripped of leaves, and I shall die," So it is with the great tree of being. Nothing is completely and merely individual.

He is a poor son whose sonship does not make him desire to serve all men's mothers.

One never finds life worth living. One always has to make it work living.

The stars are not so strange as the mind that studies them, analyzes their light, and measures their distance.

Every human life involves an unfathomable mystery, for man is the riddle of the universe, and the riddle of man in his endowment with personal capacities.

The more we know about this universe, the more mysterious it is. The old world that Job knew was marvelous enough, and his description of its wonders is among the noblest poetry of the race, but today the new science has opened to our eyes vistas of mystery that transcend in their inexplicable marvel anything the ancients ever dreamed.