"It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change."

"The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind—such were our ancestors."

"The love of experiment and the patient observation of nature are the two great qualifications for a naturalist."

"If I had my life to live over again, I would have made a rule to read some poetry and listen to some music at least once every week."

"One day, on looking at an orchid, I was struck with the idea that the structure of the flower was adapted to the visits of insects."