The only possibly habitable bodies by what or whom? You have been watching too much Star Trek and assume any extraterrestrial life elsewhere could resemble that of the earth in any fashion, or that the conditions of the cosmos are in any way relative to that in our proximity or in our dimension.
We have just barely explored a few small acres on our own moon, still haven't mastered our own ocean depths... You want to define what life is, how big or how small it is, and where it can survive for the entire breadth of universe?
Pretentious and illogical... a witch doctor proclaiming taboos...
I am tired of the evolutionists playing God with education.
Actually the only people I know who speculate groundlessly on life with entirely different chemical properties than ours are teenage boys who like to watch lots of "science" fiction.
If you can propose a functional system that doesn't require carbon and liquid water there are a lot of people that would be quite interested.