Mathematics seems to endow one with something like a new sense.

I have been speculating last night what makes a man a discoverer of undiscovered things; and a most perplexing problem it is. Many men who are very clever - much cleverer than the discoverers - never originate anything.

I would give absolutely nothing for the theory of Natural Selection, if it requires miraculous additions at any one stage of descent.

The theory which I would offer, is simply, that as the land with the attached reefs subsides very gradually from the action of subterranean causes, the coral-building polypi soon raise again their solid masses to the level of the water: but not so with the land; each inch lost is irreclaimably gone; as the whole gradually sinks, the water gains foot by foot on the shore, till the last and highest peak is finally submerged.

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

I am a firm believer, that without speculation there is no good and original observation.

Even people who aren’t geniuses can outthink the rest of mankind if they develop certain thinking habits.