"Hindsight is 20/20." It's a popular saying, which captures the felt sense when you look back and see things that you couldn't possibly have seen (or failed to notice) in the past. That person you married who seemed so perfect but turned out to be an asshole — if only you'd known, right?
The thing about this truism, though, is that it's just not true. Hindsight isn't perfect — it's not even close. Here are a few of the ways that hindsight can mislead us and distort our perspective.
We can't see alternative pasts
So you married Mx. Wrong, and looking back, you regret your decision. You rejected someone else who seemed kind of boring, but at least they would have treated you better. (You think.)
It's easy to make assumptions like this. If something goes badly in the past, we naturally assume that things would have gone better if only we had done something different. Much of the time we might not even be aware we're assuming anything there. But we are, and the assumption might not be correct. The truth is, we don't know how things would have gone if we'd done something different. Mx. Better might have turned out to be Mx. Worse.
In high school I was a pretty good saxophonist. In college I let it drop, and when I came back to it a couple decades later I found a teacher who told me, "you could have been really great" (i.e., if I had maintained serious study in my youth, the implication being that it was now too late for greatness).
It's tempting to think that I "should have" gone to music school, practiced the saxophone intensively, tried to become "great". I think it's very likely that I had more natural talent for music than I do for my current profession (software engineering management).
But who knows what would have happened if I'd chosen that path? My life would have been totally different. I wouldn't have met the lovers I've met, wouldn't have had the kids I've had, would perhaps not have prioritized my emotional development in the same way. It doesn't make any sense to regret the decisions I made, because I have literally no idea how my life would have turned out if I'd made different decisions.
Similarly, we can't see future consequences of past decisions. There's an old Taoist tale that goes:
Once upon a time there was a Chinese farmer whose horse ran away. That evening, all of his neighbors came around to commiserate. They said, “We are so sorry to hear your horse has run away. This is most unfortunate.” The farmer said, “Maybe.” The next day the horse came back bringing seven wild horses with it, and in the evening everybody came back and said, “Oh, isn’t that lucky. What a great turn of events. You now have eight horses!” The farmer again said, “Maybe.”
The following day his son tried to break one of the horses, and while riding it, he was thrown and broke his leg. The neighbors then said, “Oh dear, that’s too bad,” and the farmer responded, “Maybe.” The next day the conscription officers came around to conscript people into the army, and they rejected his son because he had a broken leg. Again all the neighbors came around and said, “Isn’t that great!” Again, he said, “Maybe.”
The point is, something has happened, something that we have labeled "good" or "bad" based on what we can see with our hindsight. But there may be more consequences of that event still to come, and since we still can't see the future, we don't know what those consequences will be (and whether they will be to our liking).
Our perspective is different, but not objective
While we're looking back with our "20/20" hindsight, we're inevitably making judgments. That person was an asshole, I would have been happier as a professional musician, eight horses are better than one. All of those judgments are based on our current views and perceptions, which filter our view of the past as much as they filter our view of the present. Sure, maybe we've learned something from the past and have more perspective now. But maybe we'll learn something else and our perspective will be different in the future. Our view of the past isn't objective just because it's the past.
I once had a long term relationship that I'd felt some considerable ambivalence about. When the relationship ended, I looked back and thought to myself, "I should have listened to my ambivalence and not made a commitment." Years later, I experienced ambivalence in other relationships and I undertook a deep exploration of what exactly constituted that ambivalence and where it was coming from. In therapy I encountered the childhood wounds and existential fears that drive me to keep a foot out the door. Now my perspective on that long-term relationship from years ago has shifted. While it remains true that it didn't work out, it seems much less clear that my ambivalence represented any kind of warning sign.
The image of our past self is distorted
This is the most paradoxical reason why hindsight isn't 20/20: we have a tendency to project our current knowledge onto the past and judge ourselves and others accordingly. I think this is what Sidney Dekker was referring to when he wrote:
"There is almost no human action or decision that cannot be made to look flawed and less sensible in the misleading light of hindsight. It is essential that the critic should keep himself constantly aware of that fact." [emphasis mine]
— Dekker, The Field Guide to Understanding Human Error
I say it's paradoxical because it means that, even if our hindsight is "correct", it distorts our perspective on the past. We are apt to believe that we (or others) "should have" acted as if we had the information we now have, even though we didn't. Our decisions appear "flawed and less sensible", although they may have been entirely sensible at the time. We judge the past through the haze of our apparent newfound clarity.
In the case of my long-term relationship, it's tempting to think that the relationship "failed" because it ended and that I "should have" seen it coming and gotten out. But this is an impoverishing perspective, which obscures all the goodness that existed in the relationship for many years, and all the ways in which it helped me grow into the person I am today.
Why does it matter?
It would be easy, but foolish, to take this argument to an extreme and suggest that we cannot learn from experience. It's often useful to reflect on the past. However, we do a disservice when we judge past decisions harshly. We may blame others unreasonably, or our own self-judgment may cloud our vision and actually impair our ability to usefully reflect and learn.
This applies to how we think about the future, too. For many years I've been reasonably good at not regretting the past. But I've still put a lot of pressure on myself about decisions that might impact the future. (This is one reason I often struggle with ambivalence — I'm worried about making the "wrong" choice.) Lately I've been trying to remind myself that I will never know whether a choice was "right", and that based on past experience I'm unlikely to seriously regret whatever choice I make. This doesn't mean that I stop trying to make good choices, but it does mean that I can spend a lot less energy worrying about it, and spend less time in decision paralysis.
The point here is to avoid getting stuck in judgment and fear, which constrain our perspective. Instead, we can approach learning and decision-making from a spirit of curiosity. We can acknowledge the sensibility of our past decisions in light of the situation we were in and what we knew then. Indeed, by reflecting on the situational appropriateness and intelligence of past actions we may learn things that we cannot learn simply by focusing on mistakes. We can also apply our curiosity to the apparent misfortunes and mistakes, asking ourselves what there is to be learned, while holding our judgments lightly and remembering that we undoubtedly still have more to learn. Knowing this, we can move through life with greater lightness and freedom.