I think if we had the smallest space, the tiniest that one can imagine. We can do it as long as we have access to outside, nature, parks or wandering the streets, they will all compensate to give us that room to 'breathe'.
The question is, what if for some duration of time we don't have access to outside, how much room is enough for anyone to live mentally and emotionally well.
One room, studio?
Two room apartment?
a house with no backyard?
a house with backyard?
ofcourse the sky's the limit..but how little can we manage to maintain our mental well being?