Men and other animals _vary_ in their natures and mental faculties quite as much as they do in colour, size, and shape. It is commonly supposed that the mental and temperamental variety existing among individual men does not exist among individual birds, quadrupeds, insects, etc. But a little observation or reflection ought to be enough to convince anyone that such a supposition belongs to that batch of pre-Darwinian mistakes presented to us by an over-generous past. We are _not acquainted_ with the inhabitants of our fields and barn-yards. We are almost as ignorant of the mental life and personality of these door-yard neighbours and friends of ours as we would be if they were the inhabitants of another continent. That is why our obtuse minds lump them together so indiscriminately—we do not know anything about them. We never take the trouble, or think it worth while, to get acquainted with them, much less to study and know them. We have grown up in the falsehood that they are altogether different from what we are, and that it is really not worth while to bother our gigantic heads about them, except to use them when it comes handy, or kick them to one side, or execute them, when they get in the way. Everybody else looks at the matter in about the same way, so we just let it go at that. There is a sameness about foreigners and other classes of _human_ beings with whom we are but slightly, or not at all, acquainted, until we come to know them and can discriminate one from another. I remember once asking my sister, if her baby, which looked to me like all other babies I had ever seen, were mixed up with a lot of other babies of about the same age, whether she could pick hers out from all the rest, and she gave me an unmistakable affirmative by answering, ‘What a foolish question!’