I have tried lately to read Shakespeare, and found it so intolerably dull that it nauseated me."

I must begin with a good body of facts and not from a principle (in which I always suspect some fallacy) and then as much deduction as you please.

The very essence of instinct is that it's followed independently of reason.

"I have steadily endeavoured to keep my mind free so to give up any hypothesis, however much beloved (and I cannot resist forming one on every subject), as soon as facts are shown to be opposed to it."

"Believing as I do that man in the distant future will be a far more perfect creature than he now is, it is an intolerable thought that he and all other sentient beings are doomed to complete annihilation after such long-continued slow progress."