When some state or other offered Alexander a part of its territory and half of all its property he told them that 'he hadn't come to Asia with the intention of accepting whatever they cared to give him, but of letting them keep whatever he chose to leave them.' Philosophy, likewise, tells all other occupations: 'It's not my intention to accept whatever time is leftover from you; you shall have, instead, what I reject.' Give your whole mind to her.
Seneca the YoungerSome there are that torment themselves afresh with the memory of what is past; others, again, afflict themselves with the apprehension of evils to come; and very ridiculously both - for the one does not now concern us, and the other not yet ... One should count each day as a separate life.
Seneca the Younger