Epicurus says, "gratitude is a virtue that has commonly profit annexed to it." And where is the virtue that has not? But still the virtue is to be valued for itself, and not for the profit that attends it.
Seneca the YoungerIt is man's duty to live in conformity with the divine will, and this means, firstly, bringing his life into line with 'nature's laws', and secondly, resigning himself completely and uncomplainingly to whatever fate may send him. Only by living thus, and not setting too high a value on things which can at any moment be taken away from him, can he discover that true, unshakeable peace and contentment to which ambition, luxury and above all avarice are among the greatest obstacles.
Seneca the Younger