Ignorance more frequently begets confidence than does knowledge.

I must begin with a good body of facts and not from a principle (in which I always suspect some fallacy) and then as much deduction as you please.

In however complex a manner this feeling may have originated, as it is one of high importance to all those animals which aid and defend one another, it will have been increased through natural selection; for those communities, which included the greatest number of the most sympathetic members, would flourish best, and rear the greatest number of offspring.

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

About thirty years ago there was much talk that geologists ought only to observe and not theorise; and I well remember some one saying that at this rate a man might as well go into a gravel-pit and count the pebbles and describe the colours. How odd it is that anyone should not see that all observation must be for or against some view if it is to be of any service!

The instruction at Edinburgh was altogether by lectures, and these were intolerably dull, with the exception of those on chemistry.

I cannot see ... evidence of design and beneficence ... There seems to me too much misery in the world.