I cannot persuade myself that a beneficient and omnipotent God would have designedly created...that a cat should play with mice.

Nature will tell you a direct lie if she can.

What wretched doings come from the ardor of fame; the love of truth alone would never make one man attack another bitterly.

As the sense of smell is so intimately connected with that of taste, it is not surprising that an excessively bad odour should excite wretching or vomitting in some persons.

Even people who aren’t geniuses can outthink the rest of mankind if they develop certain thinking habits.

My mind seems to have become a kind of machine for grinding general laws out of large collections of facts, but why this should have caused the atrophy of that part of the brain that alone on which the higher tastes depend, I cannot conceive. A man with a mind more highly organised or better constituted than mine would not, I suppose, have thus suffered, and if I had to live my life over again, I would have made a rule to read some poetry and listen to some music at least once every week; for perhaps the parts of my brain now atrophied would thus have been kept alive through use.

Now when naturalists observe a close agreement in numerous small details of habits, tastes and dispositions between two or more domestic races, or between nearly-allied natural forms, they use this fact as an argument that all are descended from a common progenitor who was thus endowed; and consequently that all should be classed under the same species. The same argument may be applied with much force to the races of man.