There is no upper limit to what individuals are capable of doing with their minds. There is no age limit that bars them from beginning. There is no obstacle that cannot be overcome if they persist and believe.

I was never a great amorist, though I have loved several people very deeply.

The establishment of the world community will surely exact a price – and who can tell what that price may be? – in toil, suffering and blood.

Alexander the Great changed a few boundaries and killed a few men. Both he and Napoleon were forced into fame by circumstances outside of themselves and by currents of the time, but Margaret Sanger made currents and circumstances. When the history of our civilization is written, it will be a biological history and Margaret Sanger will be its heroine.

I felt the first inkling of a thing that presently grew quite clear in my mind, that oppressed me for many days, a sense of dethronement, a persuasion that I was no longer a master, but an animal among the animals, under the Martian heel.With us it would be as with them, to lurk and watch, to run and hide; the fear and empire of man had passed away.

My days I devote to reading and experiments in chemistry, and I spend many of the clear nights in the study of astronomy. There is, though I do not know how there is or why there is, a sense of infinite peace and protection in the glittering hosts of heaven. There it must be, I think, in the vast and eternal laws of matter, and not in the daily cares and sins and troubles of men, that whatever is more than animal within us must find its solace and its hope.

Religions are such stuff as dreams are made of.