Spartan space = no clutter = low impact on the mind = equals relaxing as I see it. I can't think straight or relax in a place that is cluttered and messy.
Just did some room use shuffling here (son switched with the room we used as living room). The livingroom is currently VERY open and almost no clutter at all. Veeeery relaxing in there right now. Son's room is the usual mess
but I don't need to live in his room thankfully.
And the science answer, is to ponder, what is beyond the light barrier limit?
If the universe is 13 billion years old, and that means you won't be seeing light any further than 13 billions years distant, what would you be looking at past that point? Just a lot of blank black nothingness?