@elemtilas Humans are animals and everything you do with animals, you can do with human.

When you compare pugs to wolves, you realize that the Habsburg were still pretty fine, compared to what can be achieved if you really go for it.

@StarfishPrime I'm sure we could find loads of explications for a universe in which people prefer to eat artificial meat than real meat. But that's not the topic of that question.

You wrote the answer in your question "the artificial versions aren't quite the same". If you have a choice between artificial and non artificial, but artificial is worse, why would people pick it ?

They might lose a few cities but when all your officers in the controlled cities are assassinated; and a few weeks after the start of the war your country leaders are too... then maybe you decide it might not have been a good idea to attack the magically sneaky elves.

When your children are adults, they'll be on their own and have to push through life's suffering alone. That's why you need to train them in a controlled environment to be independant. So maybe that's what God is doing. The world these people live in is only a preparation for a next step where their God won't be able to interveine. He has to let some suffering in.

@DavidK "For the moon to [...]" --> That's a reformulation of my answer yes. I didn't say the other planet was on the same orbit, I said it was on the same radius, as in, on a same line leaving the sun, behind the occupied planet. So yeah, on a bigger orbit too.

@NuclearHoagie That's why I added the PS. If we want the planet to appear the same size the moon appears to us, I don't think it'd be stable.

@Vilx- You run up the stairs and jump very hard! Duh.

Since OP's question starts from something that doesn't exist (artificial gravity), any question about an evolution of that concept can't be answered any other way than "if you want".

This doesn't answer that we probably can indeed clone humans.

OP's question specifically talks about a '0$ bill', which would only happen with unlimited free energy. So I maintain that solar power is not a good analogy.

Solar energy isn't efficient at the scale of a country and individuals need to pay quite a bit upfront (as you said). The fact that it kinda reimburse itself up after 20 years is not a good argument to say its free. It's like saying that buying a house is free because you can sell it later at higher cost and completely reimburse yourself. Free unlimited energy is being able to let all your electrical apparels on all the time because there's no bill at the end. Unlimited light, warm water, warm or cold air in your house, car battery... We definitely can't have that through solar power.

Solar power is not free, is pretty expensive to exploit and isn't very efficient. I don't think it's a good comparison to what OP has in mind.

I don't think this is a great answer. Most of the time when people ask "I want a reason for this" people say "it's fantasy, just do it if it's cool". Here OP just ask if some end result is practical, the fact that it wouldn't appear in a realistic setting shouldn't really matter.