To keep doing it for longer. Eventually, external resources would be required regardless. I'm not betting on the current human race being capable of this, tho

To keep doing it for longer. Eventually, external resources would be required regardless. I'm not betting on the current human race being capable of this, though-- in my opinion, we will need to more or less become a different species for anything like civilization as we know it to survive over the very long term. Otherwise we will inevitably keep wasting too much energy on emotionally driven, incredibly stupid and violent conflicts with each other.