The Prince by Niccolo Machiavelli Chapter 21 Page 6

But when you pronounce valiantly in favour of one side or other, if he to whom you give your adherence conquers, although he be powerful and you are at his mercy, still he is under obligations to you, and has become your friend; and none are so lost to shame as to destroy with manifest ingratitude, one who has helped them. Besides which, victories are never so complete that the victor can afford to disregard all considerations whatsoever, more especially considerations of justice. On the other hand, if he with whom you take part should lose, you will always be favourably regarded by him; while he can he will aid you, and you become his companion in a cause which may recover.

In the second case, namely, when both combatants are of such limited strength that whichever wins you have no cause to fear, it is all the more