There is no absurdity in theology so great that you cannot parallel it by a greater absurdity in Nature.

. . . I fail to find a trace [in Protestantism] of any desire to set reason free. The most that can be discovered is a proposal to change masters. From being a slave of the papacy, the intellect was to become the serf of the Bible.

People never will recollect that mere learning and mere cleverness are of next to no value in life, while energy and intellectual grip, the things that are inborn and cannot be taught, are everything.

The method of scientific investigation is nothing but the expression of the necessary mode of working of the human mind.

... our "Physick" and "Anatomy" have embraced such infinite varieties of being, have laid open such new worlds in time and space, have grappled, not unsuccessfully, with such complex problems, that the eyes of Vesalius and of Harvey might be dazzled by the sight of the tree that has grown out of their grain of mustard seed.

It seems safe to look forward to the time when the conception of attractive and repulsive forces, having served its purpose as a useful piece of scientific scaffolding, will be replaced by the deduction of the phenomena known as attraction and repulsion, from the general laws of motion.

The best men of the best epochs are simply those who make the fewest blunders and commit the fewest sins.