Verified by 
Make it a rule of life never to regret and never to look back. Regret is an appalling waste of energy; you can't build on it; it's only for wallowing in.
Katherine Mansfield
My one regret in life is that I am not someone else.
Woody Allen
I recently suggested that having a bad conscience is foolish. This is not a novel idea. Nietzsche had it. Once the bad conscience is gone, what about regret? Like guilt, regret involves self-recrimination and the sense that you could have and should have acted differently. So this could be the end of the post: Believing that a bad conscience is for suckers, I must also believe that regret is.
Before closing the book, let's take another look, shall we? Let's not dismiss lightly a sentiment as pervasive and fundamental as regret. Evolutionists will surely tell a tale of how adaptive regret is even if they cannot marshal evidence that regret is uniquely human (Mr Hauser, care to comment?). Economists have come to love regret as a tool to repair their axiomatic model of rationality, which is under attack from Danny Kahneman and other Nobel laureates in their discipline.
Psychologists tend to take the experience of regret as a given, and occupy themselves with the study of its antecedents, consequences, and boundary conditions. They find, for example, that short-term regret is focused on things we did rather than did not do, whereas long-term regret shows the reverse pattern. If you're over fifty, please get busy on your bucket list. This is all very interesting, but it is business as usual. Why do we feel regret in the first place, and should we?
Regret springs from the wish to undo an earlier decision. Why? Typically, we feel regret when-and because-we have obtained new information. I ate the Bratwurst cum Sauerkraut at midnight. At 3 a.m. I threw up. At 3.05 a.m. I felt regret. I should have resisted the lure of this quintessentially Teutonic delight. I (feel I) know that I could have acted differently; I could have chosen the fragrant French herb salad as a late-night snack. Alas, I cannot undo an earlier decision après le vomissement. Time travel remains the stuff of science fiction. Regret is a form hindsight bias: the irrational idea of having seen it coming when we didn't.
Ditto for long-term regret. As you prepare to "get low," you wish you had chosen to have kids instead of selfishly spending your dime on travels to Angkor Wat and Macho Grande. Again: Too late! Plus, you are only assuming you'd be happy if you had chosen a different path because, as it has turned out, you are miserable now. This is not exactly a case of hindsight bias, but of outcome bias. Rationally, you'd evaluate a decision from the perspective available to the decision maker at the time the decision maker made the decision.
Hindsight bias, outcome bias, criteria of rationality: there is enough conventional insight in psychological science that forces the conclusion for which I named this post: Forget regret.
So why don't we?
We don't because regret is a moral emotion, and moral emotions cut to the limbic system. They allow us to condemn others. Wait! Regret is a condemnation of self, not others. Yes, seemingly. To untangle this knot, I ask you to revisit Nietzsche with me. Nietzsche opposed the notion of free will with adamantine resolve. Remember that he understood the induction of guilt as a religious (Christian in particular) con game by which ordinary people are given (a) demanding and decontextualized moral precepts (thou shalt not do this or that whatever the circumstances) and (b) the idée fixe that they can choose what they will want and what they will do. If, however, determinism is the game of the universe, individual human beings will soon violate the moral code only to then fault themselves for their transgressions. They could have, they tell themselves, resisted temptation and not do the selfish thing.
Nietzsche's analysis applies to regret. The sense that "I could have acted differently" is code for "I should have acted differently." Free will is a doctrine inculcated to make you act for the benefit of others (society). Society (religion) plays a trick on you by getting you to believe in free will so you may be held responsible. As the moral code and the doctrine of free will are internalized, they become a means of social control.
Isn't that supremely ironic? What controls you is the belief that you are not controlled! This is why regret (just like guilt) is called a moral emotion. A moral emotion is an emotion related to the welfare of others, not yours. The "should" appears with such force in your mind because you have internalized the demands of others. And you are pleased with yourself. You proudly note that you are not a psychopath.
Regret is not so ennobling, really. It can have some rather nasty consequences, and not only for you, but for others. Consider a situation affording either trust or distrust. Case 1: You trust Oliver but Oliver betrays you. You regret that you trusted him (note the hindsight bias) and resolve never to trust him again (or others who remind you of Oliver). Case 2: You distrust Stanley and then learn that Stanley would have honored your trust if you had only given him the chance to demonstrate his trustworthiness. You resolve to be more trusting in the future.
Notice the asymmetry here: Case 1 affords clear feedback, and the regret-induced change in your strategic behavior is, on balance, bad for you and your social niche. Case 2 affords no clear feedback, and the potentially salutary consequences of regret will probably be realized only in fragmentary form. Overall, regret does damage to you and society.
Much as I kvetched about Mr. Shu's self-help workshop in my first essay on this blog, I think he got one thing right. Let the past be the past, he says. Bless it. You did the best you could. Don't let regret drag you down like an iron anchor. Parting company with Shu, however, I counsel against replacing regret with the Panglossian "I-acted-like-a-churl-but-see-how-wonderfully-things-have-turned-out" heuristic. Don't bury the past selectively. Just bury it.
Research by Carsten Wrosch and colleagues and by Neil Roese and colleagues has linked intense or repetitive regret to depression and anxiety. Such findings are consistent with the dim view I have taken here. To be sure, though, there is also research in praise of regret. Especially, when regret is brief and not too intense, it might serve as a signal to act differently in the future (e.g., be more trusting). A few years ago, Melissa Acevedo and I found that people who did not vote in an election that their favored party lost felt more regret and expressed stronger intentions to vote in the next election. Whether or not voting is a rational political act is still being debated, though.
Note. When I wrote this post I was unaware that the phrase "forget regret" is found in the musical Rent. The line is "Forget regret or life is yours to miss or life is your to miss. No other road other way, no day but today." Indeed.
