"Capacity for the nobler feelings is in most natures a very tender plant, easily killed, not only by hostile influences, but by mere want of sustenance."

"He who lets the world, or his own portion of it, choose his plan of life for him, has no need of any other faculty than the ape-like one of imitation."

"He who knows only his own side of the case knows little of that."

"The principle itself of dogmatic religion, dogmatic morality, dogmatic philosophy, is what requires to be rooted out."

"The whole of mankind has a right to the benefit of the best ideas, which can only be produced by freedom of thought."