Nature will tell you a direct lie if she can.

I am dying by inches, from not having any body to talk to about insects.

It's not the strongest, but the most adaptable that survive.

The man who walks with Henslow.

The impossibility of conceiving that this grand and wondrous universe, with our conscious selves, arose through chance, seems to me the chief argument for 
the existence of God.

Whenever I have found that I have blundered, or that my work has been imperfected, and when I have been contemptuously criticised, and even when I have been overpraised, so that I have felt mortified, it has been my greatest comfort to say hundreds of times to myself that 'I have worked as hard as I could, and no man can do more than this.'

The following proposition seems to me in a high degree probable—namely, that any animal whatever, endowed with well-marked social instincts, the parental and filial affections being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man. For, firstly, the social instincts lead an animal to take pleasure in the society of its fellows, to feel a certain amount of sympathy with them, and to perform various services for them.