against the division of duties above adopted consists in setting over against that end a supposed obligation to study my own (physical) happiness, and thus making this, which is my natural and merely subjective end, my duty (and objective end). This requires to be cleared up.

Adversity, pain, and want are great temptations to transgression of one's duty; accordingly it would seem that strength, health, a competence, and welfare generally, which are opposed to that influence, may also be regarded as ends that are also duties; that is, that it is a duty to promote our own happiness not merely to make that of others our end. But in that case the end is not happiness but the morality of the agent; and happiness is only the means of removing the hindrances to morality; permitted means, since no one has a right to demand from me