About weak points [of the Origin] I agree. The eye to this day gives me a cold shudder, but when I think of the fine known gradations, my reason tells me I ought to conquer the cold shudder.

Blushing is the most peculiar and the most human of all expressions. Monkeys redden from passion, but it would require an overwhelming amount of evidence to make us believe that any animal could blush.

It is scarcely possible to doubt that the love of man has become instinctive in the dog.

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

...I have always maintained that, excepting fools, men did not differ much in intellect, only in zeal and hard work; and I still think there is an eminently important difference.

When the sexes differ in beauty, in the power of singing, or in producing what I have called instrumental music, it is almost invariably the male which excels the female.

One hand has surely worked throughout the universe.