Once, during an existential crisis, I saw an opportunity to become a step-dad, and I did. I suppose you could say that I talked myself into making it my primary purpose in life. That wasn't hard, though--working hard to make sure a kid without a father has a reasonably happy early life is about as close to perfectly meaningful as you can get.

There are a lot of problems in our society with being a step-father, and though I'll say I did a great job, I rarely hear from said kids. That's life, but what I did is "in the bank" in my way of thinking, and it's perhaps my proudest accomplishment.

For philosophical reasons, I don't think most (if any) people should have kids. But once they're here, they're as worthy a cause as anything else I know of.

(Unfortunately, too old to do it again, and meaning has become a struggle again.)