4. _Physical cravings, or appetites, have limited objects: the objects of psychical desires may be unlimited._ A thirsty man thirsts not for an ocean, but for drink _quantum sufficit_: give him that and the appetite is gone. But the miser covets all the money that he can get: the voluptuary ranges land and sea in search of a new pleasure: the philosopher ever longs for a higher knowledge: the saint is indefatigable in doing good. Whatever a man takes to be an end in itself, not simply a means, that he desires without end or measure. What he desires as a means, he desires under a limitation, so far forth as it makes for the end, so much and no more. As Aristotle says of the processes of art, "the end in view is the limit," [Greek: peras to telos] (cf. c. ii., s. iii., n. 3, p. 15) Whatever is desired as an end in itself, is taken to be a part of happiness, or to represent happiness. Happiness and the object that gives happiness is the one thing that man desires for itself, and desires without end or measure. Unfortunately he is often mistaken in the choice of this object. He often takes for an end what is properly only a means. They "whose god is their belly," have made this mistake in regard of the gratification of appetite. It is not appetite proper that has led to this perversion, but psychical desire, or appetite inflamed by the artificial stimulus of imagination. For one who would be temperate, it is more important to control his imagination than to trouble about his appetite. Appetite exhausts itself, sometimes within the bounds of what is good for the subject, sometimes beyond them, but still within some bounds; but there is no limit to the cravings bred of imagination. 5. By this canon a man may try himself to discover whether or not a favourite amusement is gaining too much upon him. An amusement is properly a means to the end, that a man may come away from it better fitted to do the serious work of his life. Pushed beyond a certain point, the amusement ceases to minister to this end. The wise man drops it at that point. But if one knows not where to stop: or if when stopped in spite of himself, he is restless till he begin again, and never willingly can forego any measure of the diversion that comes within his reach, the means in that case has passed into an end: he is enslaved to that amusement, inasmuch as he will do anything and everything for the sake of it. Thus some men serve pleasure, and other men money.