From David Allen's newsletter, a notion which combines time management and philosophy of mind (plus maybe mindfulness):

Your mind doesn't have one. A mind, that is. If your mind were smart, it would only remind you of something when you could do something about it.

That is, when there's something you need to remember — especially something you need to remember to do at a point in the future — write it down so you don't have to try to hold it in your head. As Allen says in the introduction to his little essay:

If all you get from the GTD methodology is to retire your mind from the job of being your list manager, you'd be light years ahead of most people on the planet. It's one of the easiest principles to implement, and probably one of the most common to disregard in terms of how powerful it can be. Do yourself a favor—get smarter than your mind. It would love to let go of this stuff; it's simply afraid you don't have a better servant.

(cf. Mind Like Water (2011-12-24), Getting Things Done - Summarized (2012-05-14), ...) - ^z - 2012-10-06