First of all, in approaching this subject it is well to recall to mind the undeniable fact, that a distinction in foods as clean and unclean, that is, fit and unfit for man's use, has a very deep and apparently irremovable foundation in man's nature. Even we ourselves, who stumble at this law, recognise a distinction of this kind, and regulate our diet accordingly; and also, in like manner, feel, more or less, an instinctive repugnance to dead bodies. As regards diet, it is true that when the secondary question arises as to what particular animals shall be reckoned clean or unclean, fit or unfit for food, nations and tribes differ among themselves, as also from the law of Moses, in a greater or less degree; nevertheless, this does not alter the fact that such a distinction is recognised among all nations of culture; and that, on the other hand, in those who recognise it not, and who eat, as some do, without discrimination, whatever chances to come to hand,--insects, reptiles, carrion, and so on,--this revolting indifference in the matter of food is always associated with gross intellectual and moral degradation. Certainly these indisputable facts should suffice to dispose of the charge of puerility, as sometimes made against the laws of this chapter. And not only this, but more is true. For while even among nations of the highest culture and Christian enlightenment many animals are eaten, as, _e.g._, the oyster, the turtle, the flesh of the horse and the hog, which the law of Moses prohibits; on the other hand, it remains true that, with the sole exception of creatures of the locust tribe, the animals which are allowed for food by the Mosaic code are reckoned suitable for food by almost the entire human family. A notable exception to the fact is indeed furnished in the case of the Hindoos, and also the Buddhists (who follow an Indian religion), who, as a rule, reject all animal food, and especially, in the case of the former, the flesh of the cow, as not to be eaten. But this exception is quite explicable by considerations into which we cannot here enter at length, but which do not affect the significance of the general fact. And, again, on the other hand, it may also be said that, as a general rule, the appetite of the great majority of enlightened and cultivated nations revolts against using as food the greater part of the animals which this code prohibits. Birds of prey, for instance, and the carnivora generally, animals having paws, and reptiles, for the most part, by a kind of universal instinct among cultivated peoples, are judged unfit for human food.