If we have no idea what it is, and no way to detect it, then does the category have any meaning or significance? Why aren't we worried about how "florp" everyth

If we have no idea what it is, and no way to detect it, then does the category have any meaning or significance? Why aren't we worried about how "florp" everything in the universe is, where "florp" is a mysterious, non-detectable, seemingly incomprehensible property?