there are excellent substitutes for personally having a child (e.g. convincing a less altruistic couple to have another child).
Not all children are of equivalent social benefit. If a pure altruist could make a copy of themselves at age 20, twenty years from now, for the low price of 20% of their time-discounted total social benefit—well, depending on the time-discount of investing in the future, it seems like a no-brainer.
Well, unless the descendants also use similar reasoning to spend their time-discounted total social benefit in the same way. You have to cash out at some point, or else the entire thing is pointless.
Sure, your children can be altruists, but would raising your children have highest marginal return? You only “win” by the amount of altruism your child has above the substitute child. So if you’re really good at indoctrinating children with altruism, you would better exploit your comparative advantage by spending your time indoctrinating other people’s children while their parents do the non-altruistic tasks of changing diapers, etc. Children are an efficient mechanism for spreading your genes, but not the most efficient mechanism for spreading your memes.
Not all children are of equivalent social benefit. If a pure altruist could make a copy of themselves at age 20, twenty years from now, for the low price of 20% of their time-discounted total social benefit—well, depending on the time-discount of investing in the future, it seems like a no-brainer.
Well, unless the descendants also use similar reasoning to spend their time-discounted total social benefit in the same way. You have to cash out at some point, or else the entire thing is pointless.
Sure, your children can be altruists, but would raising your children have highest marginal return? You only “win” by the amount of altruism your child has above the substitute child. So if you’re really good at indoctrinating children with altruism, you would better exploit your comparative advantage by spending your time indoctrinating other people’s children while their parents do the non-altruistic tasks of changing diapers, etc. Children are an efficient mechanism for spreading your genes, but not the most efficient mechanism for spreading your memes.