food; if they are conquered, it was poison; but if it is a drawn battle, the article is medicine. To a certain extent, this theory certainly embraces truth; although it is equally certain that it does not cover the whole ground of therapeutics and hygiene.
Pastimes and games are justified to the moral sense by their sanitary value. Cards, dominoes, and the backgammon-board are as manifestly means of health as hair mattresses and ventilating-flues. The dice-box, as used in backgammon, is often more valuable to an invalid than the pill-box. But the very fact that games are thus valuable as medical agents, proves that they can not be a wholesome article of diet; they are not valuable enough to be made a continual occupation; they do not furnish sufficient food to the mind. So far as that, we might apply the Liebig theory to them. If a man were, for example, to take up chess after the manner of Paul Morphy, master all the possible combinations so thoroughly as to be able to checkmate every adversary, and that, with any pawn designated by lot, at the beginning of the game, such a man would evidently have made more than a pastime of chess. It would have been food for his mind; just as really food, although not so valuable, as Euclid's "Elements," or Legendre's "Theory of Numbers." If, on the other hand, a man, without Morphy's talent for chess, should become infatuated with the ambition of gaining Morphy's skill, and should spend a disproportionate amount of time playing, his right hand against his left, then to him the game would be poison. Its sanitary use, as a recreation, is evidently attained only when a man pursues it just far enough to divert his mind completely from the thoughts which were injuring him, and not far enough to make it in itself an absorbing occupation.
The late Prof. Peirce once said that no game, and no toy, ever became permanently popular unless it involved some deep and peculiar mathematical or mechanical principle. He asserted it as a fact of observation, but we never heard him attempt to account for it. The theory which we are ascribing to Liebig furnishes a partial explanation. The presence of this deeper principle, underlying the game, prevents it from being digestible by any except those of strong power. To all others the game may be considered either as a poison, when it is utterly beyond their reach to do anything with it, or else it is a recreation of permanent sanitary value; that is, when the patient can acquire skill in it, but is not tempted to try to fathom its mathematical principle. Pierce's meaning may be illustrated by familiar examples. The child's top, his hoop, his bandelor, his devil on two sticks, all involve the same fundamental doctrines of rotation on an instantaneous axis, which task the mightiest powers of the geometer in their application to celestial mechanics. Ball-playing, quoits, hurling of spears, throwing
