The age-old and noble thought of 'I will lay down my life to save another,' is nothing more than cowardice.

... not one living species will transmit its unaltered likeness to a distant futurity.

Multiply, vary, let the strongest live and the weakest die.

I have just finished my sketch of my species theory. If as I believe that my theory is true & if it be accepted even by one competent judge, it will be a considerable step in science. I therefore write this, in case of my sudden death, as my most solemn & last request, which I am sure you will consider the same as if legally entered in my will, that you will devote 400£ to its publication & further will yourself, or through Hensleigh [Wedgwood], take trouble in promoting it.

I liked the thought of being a country clergyman. Accordingly I read with care Pearson on the Creed and a few other books on divinity; and as I did not then in the least doubt the strict and literal truth of every word in the Bible, I soon persuaded myself that our Creed must be fully accepted.

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.

Besides love and sympathy, animals exhibit other qualities connected with the social instincts which in us would be called moral.