"We currently have the ability to turn reproduction off. Yet many people go to extraordinary lengths to turn reproduction on. "
This is true because there are still many good reasons to have children. I don't see any of these reasons being certain and compelling by the time intergalactic travel is possible. We haven't even scratched the surface on what technology is going to do to economics and already the maternity rate in prosperous countries is below replacement. We may well expand forever but I don't think it's at all obvious.
"If e...
I find all of these propositions questionable. It's not clear at all that they will need to (1) reproduce (2) relocate or (3) capture an absurd amount of free energy. We can speculate they might want to do any of those but the arguments that they won't seem just as strong.
I highly doubt there will be any disagreement about the merits and needs of colonization within a civilization capable of intergalactic travel - it will either be a good idea and they will agree or it will be a bad idea and they will agree not to.
Seeing no evidence of colonization (...
"Children have gone from being productive capital goods to consumption goods. I don't see any evidence that children are losing or will lose their value as consumption goods."
Wait -- the value of children recently changed fundamentally but we should expect no more change far in the future?
"I'm saying that the zero population growth faction will be a tiny minority by the time a civilization grows large and advanced."
This does not reconcile at all with current population trends of developed nations. The UN medium projection for 2050 has... (read more)