Diogenes Laertius, Book II Aristippus
The school of Anniceris in other respects agreed with them, but admitted that friendship and gratitude and respect for parents do exist in real life, and that a good man will sometimes act out of patriotic motives. Hence, if the wise man receive annoyance, he will be none the less happy even if few pleasures accrue to him. The happiness of a friend is not in itself desirable, for it is not felt by his neighbour. Instruction is not sufficient in itself to inspire us with confidence and to make us rise superior to the opinion of the multitude. Habits must be formed because of the bad disposition which has grown up in us from the first. 97. A friend should be cherished not merely for his utility – for, if that fails, we should then no longer associate with him – but for the good feeling for the sake of which we shall even endure hardships. Nay, though we make pleasure the end and are annoyed when deprived of it, we shall nevertheless cheerfully endure this because of our love to our friend.