For this reason it may be judged never to be allowable for a son to disown his father, whereas a father may his son: because he that owes is bound to pay; now a son can never, by anything he has done, fully requite the benefits first conferred on him by his father, and so is always a debtor. But they to whom anything is owed may cast off their debtors: therefore the father may his son. But at the same time it must perhaps be admitted, that it seems no father ever _would_ sever himself utterly from a son, except in a case of exceeding depravity: because, independently of the natural Friendship, it is like human nature not to put away from one’s self the assistance which a son might render. But to the son, if depraved, assisting his father is a thing to be avoided, or at least one which he will not be very anxious to do; most men being willing enough to receive kindness, but averse to doing it as unprofitable. Let thus much suffice on these points. BOOK IX Chapter I. Well, in all the Friendships the parties to which are dissimilar it is the proportionate which equalises and preserves the Friendship, as has been already stated: I mean, in the Social Friendship the cobbler, for instance, gets an equivalent for his shoes after a certain rate; and the weaver, and all others in like manner. Now in this case a common measure has been provided in money, and to this accordingly all things are referred and by this are measured: but in the Friendship of Love the complaint is sometimes from the lover that, though he loves exceedingly, his love is not requited; he having perhaps all the time nothing that can be the object of Friendship: again, oftentimes from the object of love that he who as a suitor promised any and every thing now performs nothing. These cases occur because the Friendship of the lover for the beloved object is based upon pleasure, that of the other for him upon utility, and in one of the parties the requisite quality is not found: for, as these are respectively the grounds of the Friendship, the Friendship comes to be broken up because the motives to it cease to exist: the parties loved not one another but qualities in one another which are not permanent, and so neither are the Friendships: whereas the Friendship based upon the moral character of the parties, being independent and disinterested, is permanent, as we have already stated.