The greatest loss of time is delay and expectation, which depend upon the future. We let go the present, which we have in our power, and look forward to that which depends upon chance, and so relinquish a certainty for an uncertainty.
Seneca the YoungerThere is nothing that we can properly call our own but our time, and yet everybody fools us out of it who has a mind to do it. If a man borrows a paltry sum of money, there must needs be bonds and securities, and every common civility is presently charged upon account. But he who has my time thinks he owes me nothing for it, though it be a debt that gratitude itself can never repay.
Seneca the Younger