✔ 最佳答案
As it was explained to me, any "entity" is either expanding or contracting. Nothing is ever static. The entity known as "humanity" is therefore either expanding or contracting. I prefer expanding, personally. If we are to continue to expand, then sooner or later, we have to colonize space. (The final frontier).
Cheers
參考: Popular Physicist Michio Kaku, PhD, has said that Earth life is so precious, we need to be a two planet (or more) species, to ensure our survival from extinction.