From
The Discourses of Epictetus (4.12):
What, is it possible thenceforth to be entirely free from fault? No, that is beyond us; but this at least is possible: to strive without cease to avoid committing any fault. For we must be contented if, by never relaxing our attention, we manage to escape a small number of faults. But now, when you say, ‘From tomorrow I’ll pay attention,’ be clear that what you’re really saying is, ‘Today I’ll be shameless, importunate, and mean-spirited; it will lie within the power of others to cause me distress; I’ll lose my temper today; I’ll fall prey to envy.’ See how many evils you’re bringing down on yourself. But if it would be good for you to pay attention tomorrow, how much better it would be to do so today, so that you may be able to achieve the same tomorrow also, and not put it off once again until the following day.
And from Ben Franklin, in
Poor Richard's Almanack:
To-morrow I’ll reform, the fool does say;
To-day itself’s too late; - the wise did yesterday.
