Why do people think it intelligent to say, ‘I can see no difference!’ It is nowadays quite a mark of culture to say that one can see no difference between a man and a woman, or a man and an angel, or a man and an animal. If a man cannot see the difference between a horse and a cow across a large field, we do not call him cultured; we call him short-sighted. Now, there are really interesting differences between angels and women; nay, even between men and beasts, and all such things. They are differences which most people know instinctively, as most people know a cow is not a horse without looking for its mane; or most people know a horse is not a cow without looking for horns. Whether the difference ought to count in this or that important question is a completely different matter, but it ought not really to be so difficult simply to see the difference… [T]his is a strange epoch; and while, in some ways, we have quite dangerously encouraged the appetites, we have quite ruthlessly crushed the instincts.
—G. K. Chesterton, Concerning those who “cannot see the difference” (1913)