XXXV. When I promise to bestow a benefit, I promise it, unless something occurs which makes it my duty not to do so. What if, for example, my country orders me to give to her what I had promised to my friend? or if a law be passed forbidding any one to do what I had promised to do for him? Suppose that I have promised you my daughter in marriage, that then you turn out to be a foreigner, and that I have no right of intermarriage with foreigners; in this case, the law, by which I am forbidden to fulfil my promise, forms my defence. I shall be treacherous, and hear myself blamed for inconsistency, only if I do not fulfil, my promise when all conditions remain the same as when I made it; otherwise, any change makes me free to reconsider the entire case, and absolves me from my promise. I may have promised to plead a cause; afterwards it appears that this cause is designed to form a precedent for an attack upon my father. I may have promised to leave my country, and travel abroad; then news comes that the road is beset with robbers. I was going to an appointment at some particular place; but my son's illness, or my wife's confinement, prevented me. All conditions must be the same as they were when I made the promise, if you mean to hold me bound in honour to fulfil it. Now what greater change can take place than that I should discover you to be a bad and ungrateful man? I shall refuse to an unworthy man that which I had intended to give him supposing him to be worthy, and I shall also have reason to be angry with him for the trick which he has put upon me. XXXVI. I shall nevertheless look into the matter, and consider what the value of the thing promised may be. If it be trifling, I shall give it, not because you are worthy of it, but because I promised it, and I shall not give it as a present, but merely in order to make good my words and give myself a twitch of the ear. I will punish my own rashness in promising by the loss of what I gave. "See how grieved you are; mind you take more care what you say in future." As the saying is, I will take tongue money from you. If the matter be important, I will not, as Maecenas said, let ten million sesterces reproach me. I will weigh the two sides of the question one against the other: there is something in abiding by what you have promised; on the other hand, there is a great deal in not bestowing a benefit upon one who is unworthy of it. Now, how great is this benefit? If it is a trifling one, let us wink and let it pass; but if it will cause me much loss or much shame to give it, I had rather excuse myself once for refusing it than have to do so ever after for giving it. The whole point, I repeat, depends upon how much the thing given is worth: let the terms of my promise be appraised. Not only shall I refuse to give what I may have promised rashly, but I shall also demand back again what I may have wrongly bestowed: a man must be mad who keeps a promise made under a mistake.