Seneca (4 BC – 65 AD) said:
It is not that we have so little time but that we lose so much. Life is long enough and our allotted portion generous enough for our most ambitious projects if we invest it all carefully. But when it is squandered through luxury and indifference, and spent for no good end, we realize it has gone before we were aware it was going.
So it is: the life we receive is not short but we make it so; we are not ill provided but use what we have wastefully. Kingly riches are dissipated in an instant if they fall into the hands of a bad master, but even moderate wealth increases with use in the hands of a careful steward; just so does our life provide ample scope if it is well managed.
Excerpt from my favorite blog: http://www.adamsmithesq.com/