in question what affinity it has with the acknowledged principles, or with the objects so delightful by the pleasure which they give him.
So that the art of persuasion consists as much in that of pleasing as in that of convincing, so much more are men governed by caprice than by reason! Now, of these two methods, the one of convincing, the other of pleasing, I shall only give here the rules of the first; and this in case we have granted the principles, and remain firm in avowing them: otherwise I do not know whether there could be an art for adapting proofs to the inconstancy of our caprices.
But the manner of pleasing is incomparably more difficult, more subtle, more useful, and more admirable; therefore, if I do not treat of it, it is because I am not capable of it; and I feel myself so far disproportionate to the task, that I believe the thing absolutely impossible.
Not that I do not believe that there may be as sure rules for pleasing as for demonstrating, and that he who knows perfectly how to comprehend and to practice them will as surely succeed in making himself beloved by princes and by people of all conditions, as in demonstrating the elements of geometry to those who have enough imagination to comprehend its hypotheses. But I consider, and it is, perhaps, my weakness that makes me believe it, that it is impossible to reach this. At least I know that if any are capable of it, they are certain persons whom I know, and that no others have such clear and such abundant light on this matter.
The reason of this extreme difficulty comes from the fact that the principles of pleasure are not firm and stable. They are different in all mankind, and variable in every particular with such a diversity that there is no man more different from another than from himself at different times. A man has other pleasures than a woman; a rich man and a poor man have different enjoyments; a prince, a warrior, a merchant, a citizen, a peasant, the old, the young, the well, the sick, all vary; the least accidents change them.
Now there is an art, and it is that which I give, for showing the connection of truths with their principles, whether of truth or of pleasure, provided that the prin-
