How can we possibly learn to do something that has the appearance of being against individual interest?

Well, here's a place to start. Why make a sacrifice? Of course, these are interrelated, but in my mind they are distinguishable cases.

-For someone else: an individual or group sacrifices for the benefit for another individual or group. (A parent commutes a longer distance so that their children can attend a better public school)

-For themselves: an individual sacrifices so they can ultimately benefit. (I sacrifice an extra helping of cake so that my health gains)

-For the future: An individual or group sacrifices so that there will be utility in the future. (A company invests in a pension fund)

Now, another assumption: this behavior is learned. Even if it's not, we make an effort to teach it, and those interventions seem like they might have a chance at forcing someone to sacrifice in an involuntary manner--which causes sacrifice to happen even if it's not dictated by the conscience of the sacrificer.

So, there are ways of sacrificing, and that behavior is [at least partially] learned or directed. There are other ways of influencing behavior, like coercion or incentives. And there are times when people sacrifice when they don't HAVE to...like giving change in your pocket to someone on the street. So why do people sacrifice when they don't have to?

Perhaps it's a question of assigning value. Maybe people see the option of sacrifice as providing more value to another person or in the long-run. This is plausible, because I'm skeptical of this suggestion because individuals as consumers have so much difficulty placing value on the choices they make or the resources they have. If value is at the core of this myster, we'd have to tepidly assume that people are extremely rational--to the point of controlling their primary urges--right?

Persuasion is another problematic explanation. Simply put, if people make sacrifices because of persuasion, they can also be persuaded out of making sacrifices or be persuaded into making bad sacrifices. Which, seems to stand up to reality I concede.

Some sacrifices seem to just happen, whcih means it's in the nature of some people in some circumstances to sacrifice or that sacrificing can be learned/cultivated.

I don't know exactly how that teaching/learning happens. I think it's by example. I just know it's important...many of our public policies will need sacrifice to be successful. When people don't sacrifice, it seems like non-optimal outcomes happens...if all that happens is take-take-take, there eventually won't be enough left to give, right?

Sheesh, what a random thought-experiment. So much for the vignettes.