Regret is a dangerous emotion. You can't act on it. What little you may learn from regret risks being fruit from a poisonous tree. Too often, regret pulls you into a space of despair.

The flavor of regret that I regularly feel is what I call "Groundhog's Day regret." The perfectionist in me fantasizes about perfectly executed stretches of time. If only I could carpe diem as Bill Murray eventually does in that classic film, I might fill a day like an expertly played game of Tetris.

But the truth is that we are actors in a hazy fog, the fog of war, the fog of life. Remove the fog with piercing hindsight and we are only watching a fictional and personal Groundhog's Day.

That is why regret is so useless — and so pernicious.

Not only can we not do anything about it, but it's a false view of the past we seek to change because no memory of the past is accurate without the fog. Without the fog of war, there is no messy battle and that messy battle is everything.

What can we learn? Is there anything we can do to avoid the poison of regret?

Maybe. Perhaps we ask ourselves some careful questions. Is there something I should have (and could have!) considered, but didn't? Could I have removed any small piece of the fog to reduce the uncertainty? Does the regret that I feel have any bearing on this moment, or am I, as before, caught in a fog and should only commit to making the best of the confusion?

In asking those questions, we ought to be mindful that we don't fall into the trappings of regret. However, if we navigate the introspection carefully, we just may find some fruitful wisdom free from contamination.