I wish that
          I knew then,
          What I know now,
When I was younger.  — Rod Stewart, Every Picture Tells a Story

Remorse and regret are not the same thing.

Remorse relates to empathy for the subject of one’s behavior. Remorse might be characterized by feeling: “What I did hurt someone else, and I caused that hurt and I feel bad about the harm I did.” It could be mild remorse, or major remorse, but it is focused on how one feels about something done to another.

Regret is personal. “I did something that has a cost to me as a result. It was a stupid thing for me to do, and now I will pay a price. I got caught, and now I will have to bear the result,” is an expression of regret. It could be a slight embarrassment, or it could be incarceration, but it is focused not on the other, but on oneself.

Remorse is useful in developing self-regulation. As a child, my parents, especially my mother, would often talk with me at length about how my (bad) behavior had led to disappointment. I recall, these many years later, crying as I sat with my mom, requesting punishment in lieu of having such a talk. I didn’t like the way I felt when it was made clear to me the results of an action or behavior. Feeling I’d disappointed my mother was terrible. I didn’t like the feeling – and made an effort to not do something else to disappoint her. I’m sure that I did, many times, but I didn’t like the feeling at all.

I suppose if I had been the kind of person that lacked the capacity for remorse, I might have felt like I got off easy having to sit through that kind of a talk. In which case, my mother or father would have had to find another way to provide guidance.

Remorse is closely akin to guilt. Guilt sometimes gets a bad rap, probably because it can be overdone. 

We live in a society in which most people can be trusted to conform to established norms, most of the time. It’s still a good idea to lock one’s doors, though, because not everyone follows the rules. Because most of us do, we live in a society that works for most of us, most of the time.

On coral reefs, there are cleaning stations that are easy to find and observe while snorkeling. A fish will visit a cleaning station, remain motionless, and allow tiny cleaner fish to pick off the parasites. The fish gets cleaned of the pests, and the cleaner fish gets a nice meal of tasty parasites.

It works for everyone. Except when cheating occurs. Sometimes a cleaner fish will take a nip out the fish being cleaned. And sometimes the fish being cleaned will eat the cleaner fish. But the vast majority of the time, the process works to mutual benefit. Even with cheaters, I would guess there’s no remorse, and no regret. After all, they’re fish.

But most of we human primates do remorse and regret very well indeed, and, feeling these things contribute to civilized society.