So highly did Franklin esteem his method that he intended to follow it up with a treatise, to be known as the _Art of Virtue_, containing a practical commentary upon each of the virtues inserted in his little book, and showing just how anyone could make himself virtuous, if he only had a mind to. In this treatise, it was his desire, he says in the _Autobiography_, to expound the doctrine that vicious actions are not hurtful because they are forbidden but forbidden because they are hurtful, the nature of man alone considered, and that it is therefore to the interest of everyone to be virtuous who wishes to be happy even in this world. "I should from this circumstance," he said, "(there being always in the world a number of rich merchants, nobility, states, and princes, who have need of honest instruments for the management of their affairs, and such being so rare), have endeavoured to convince young persons that no qualities were so likely to make a poor man's fortune as those of probity and integrity." The thought was more fully developed in a letter to Lord Kames, dated May 3, 1760. I purpose likewise [he said], a little work for the benefit of youth, to be called the _Art of Virtue_. From the title I think you will hardly conjecture what the nature of such a book may be. I must therefore explain it a little. Many people lead bad lives that would gladly lead good ones, but know not _how_ to make the change. They have frequently _resolved_ and _endeavoured_ it; but in vain, because their endeavours have not been properly conducted. To expect people to be good, to be just, to be temperate, &c., without _shewing_ them _how_ they should _become_ so, seems like the ineffectual charity mentioned by the Apostle, which consisted in saying to the hungry, the cold, and the naked, "Be ye fed, be ye warmed, be ye clothed," without shewing them how they should get food, fire, or clothing. Most people have naturally _some_ virtues, but none have naturally _all_ the virtues. To _acquire_ those that are wanting, and secure what we acquire, as well as those we have naturally, is the subject of _an art_. It is as properly an art as painting, navigation, or architecture. If a man would become a painter, navigator, or architect, it is not enough that he is _advised_ to be one, that he is _convinced_ by the arguments of his adviser, that it would be for his advantage to be one, and that he resolves to be one, but he must also be taught the principles of the art, be shewn all the methods of working, and how to acquire the habits of using properly all the instruments; and thus regularly and gradually he arrives, by practice, at some perfection in the art.