Quote Originally Posted by Illusions View Post
1. By the time we could seriously consider terraforming Mars, we will have hopefully solved our overpopulation problem here on Earth. We already have near 7 Billion people right now, and we can only educate, feed, cloth, shelter, etc. a very small percentage at what could be considered a decent level. If we need to terraform a planet to fix this we have failed horrendously as a species.
We can seriously consider it now. Really. The cost for kicking off a biologically-driven process isn't that high (not doing things like asteroid or comet drops, which would help end habitability but aren't strictly needed). It's about the same as sending rovers to Mars. We've already got and use all the technology required too - it isn't very different from sending rovers to mars. There's also already been a substantial amount of research done on which biologicals to send and in what order and time frame to produce optimal terraforming results. There are other things we can do later (solar mirrors, comet drops), but we've got a few hundred years while waiting for the process to go anyways to get around to doing those things.

2. Nothing we do has purpose except that which we give it. Turning an uninhabitable world into a habitable one to demonstrate our abilities as a species seems like a grand enough purpose in and of itself, and would be a progression of our already existing abilities to alter environments here on Earth.
I disagree. We shouldn't be doing things unless we derive some gain from it. The gain doesn't need to be tangible or direct, but I don't think prestige or ego-boosting is a good enough reason, unless we find ourselves with nigh-infinite resources and energy. Otherwise our efforts would be better directed towards things that do gain us benefits.