You need not wonder at any genius of mine; for as yet I am lavish only with other men's property. – But why did I say "other men"? Whatever is well said by anyone is mine. This also is a saying of Epicurus: "If you live according to nature, you will never be poor; if you live according to opinion, you will never be rich." Nature's wants are slight; the demands of opinion are boundless. Suppose that the property of many millionaires is heaped up in your possession. Assume that fortune carries you far beyond the limits of a private income, decks you with gold, clothes you in purple, and brings you to such a degree of luxury and wealth that you can bury the earth under your marble floors; that you may not only possess, but tread upon, riches. Add statues, paintings, and whatever any art has devised for the luxury; you will only learn from such things to crave still greater.
Natural desires are limited; but those which spring from false opinion can have no stopping-point. The false has no limits. When you are travelling on a road, there must be an end; but when astray, your wanderings are limitless. Recall your steps, therefore, from idle things, and when you would know whether that which you seek is based upon a natural or upon a misleading desire, consider whether it can stop at any definite point. If you find, after having travelled far, that there is a more distant goal always in view, you may be sure that this condition is contrary to nature.