Okay, I am going to set this aside first, I mean no harm to anyone. I love arguing and I found this as an amazing source. I hope that no one gets offended by this reply. Here goes. I disagree. I get how you can see the disadvantages in Terra-forming and off-planet colonization, however, you have to weigh the benefits as well. our planet is supporting us now, but we are quickly destroying it. This is also a point in your argument. You argue that because we have done quite a bit of damage to our own planet, we shouldn't go to another planet just to damage that one. I feel the opposite. Sure, we have done a lot of damage to this planet with things such as global warming and the extinction of many species that were thriving before we entered the equation, however, I trust the fact that humanity will do better. Scientists are already working to prevent damage to our atmosphere, which, if we colonize another planet, that knowledge will carry over, allowing us to keep the planet stable and well. For the sake of the argument, my beliefs will not factor in, and I view things on a purely scientific standpoint. You also say that there is a chance that life could exist on the planet (I realize I have not said the planets name yet, its venus), however, you have to factor in (I will use ^ to symbolize "to the power of") N = R^* times f^p times n^e times f^1 times f^1 times f^c times L. This equation is the represents the chance of life existing at the same time we exist. There is a great article for it at https://www.space.com/25219-drake-equation.html It explains all of it. All in all, the chances of life existing at the same time is tiny, incredibly tiny. It is even smaller, and I mean small, like incredibly smaller for life to form on Venus. I respect your opinion and your beliefs, but I love an argument. There is also the huge reason we will Terra-form, the sake of increasing us as a society. Every generation brings something new to the table that helps us grow. Me, one of the people representing generation z, know that eventually we will be ready to advance society, to help everyone grow. If we stay on the track we are now, our research will allow us to make life easier and simpler for the people who will be after us. If we are able to colonize a planet, we could use that planet for things that help the general person, like for farming, or energy production. All in all, on a personal note, I view the colonization of Venus, or any planet to be mutually beneficial. Wow, congrats for getting to the bottom of this. I apologize for the sheer vastness of this, I love arguments. Otherwise, I respect your argument and value your points. You made some good ones.