Far be it from me to controvert these views, if any one likes to hold them. All I wish to remark is that such a conception of the nature of "laws" has nothing to do with modern science. It is scholastic {252} realism--realism as intense and unmitigated as that of Scotus Erigena a thousand years ago. The essence of such realism is that it maintains the objective existence of universals, or, as we call them nowadays, general propositions. It affirms, for example, that "man" is a real thing, apart from individual men, having its existence, not in the sensible, but in the intelligible world, and clothing itself with the accidents of sense to make the Jack and Tom and Harry whom we know. Strange as such a notion may appear to modern scientific thought, it really pervades ordinary language. There are few people who would, at once, hesitate to admit that colour, for example, exists apart from the mind which conceives the idea of colour. They hold it to be something which resides in the coloured object; and so far they are as much Realists as if they had sat at Plato's feet. Reflection on the facts of the case must, I imagine, convince every one that "colour" is--not a mere name, which was the extreme Nominalist position--but a name for that group of states of feeling which we call blue, red, yellow, and so on, and which we believe to be caused by luminiferous vibrations which have not the slightest resemblance to colour; while these again are set afoot by states of the body to which we ascribe colour, but which are equally devoid of likeness to colour. In the same way, a law of nature, in the scientific sense, is the product of a mental operation upon the facts of nature which come under our observation, and has no more existence outside the mind than {253} colour has. The law of gravitation is a statement of the manner in which experience shows that bodies, which are free to move, do, in fact, move towards one another. But the other facts of observation, that bodies are not always moving in this fashion, and sometimes move in a contrary direction, are implied in the words "free to move." If it is a law of nature that bodies tend to move towards one another in a certain way; it is another and no less true law of nature that, if bodies are not free to move as they tend to do, either in consequence of an obstacle, or of a contrary impulse from some other source of energy than that to which we give the name of gravitation, they either stop still, or go another way.