One general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.

If every one were cast in the same mould, there would be no such thing as beauty.

There is a grandeur in this view of life, from so simple a beginning endless forms most beautiful are being evolved

I think it inevitably follows, that as new species in the course of time are formed through natural selection, others will become rarer and rarer, and finally extinct. The forms which stand in closest competition with those undergoing modification and improvement will naturally suffer most.

In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history.

During my second year at Edinburgh [1826-27] I attended Jameson's lectures on Geology and Zoology, but they were incredible dull. The sole effect they produced on me was the determination never as long as I lived to read a book on Geology.

Farewell Australia! You ... are too great and ambitious for affection, yet not great enough for respect. I leave your shores without sorrow or regret.