What happens on Mars, stays on Mars: a reply to Balistreri and Umbrello

In a previous paper published in this journal, I have claimed that the – possible – acceptance of human enhancement on Mars does not (and should not) be followed by an emulation on Earth, as these two settings are not only two different planets, but they are also two different worlds. Some critics see my position as unconvincing and unstable. Yet, I am very glad that Maurizio Balistreri and Steven Umbrello engaged with my work in such a fiercely critical manner: it has pushed me to think more intensely on what I previously wrote, helping me realize what could have been explained more clearly and in depth. Hopefully, this reply will make my position less “philosophically dubious” and will also help Balistreri and Umbrello seeing some of the flaws in their own argument. I will shape this paper in a way that will rely quite heavily on the previous exchange of views, so to be as focused as possible on how to counterargue at least some of the critiques received. Hence, I will divide the paper into three parts, each addressing one of the points raised by them. I will call those 1) the future generations critique; 2) the natural boundaries critique and 3) the continuum critique.