possibleness vs being

possibleness and being both are nouns.

Word	Noun	Adjective	Verb	Adverb
possibleness	Yes	No	No	No
being	Yes	No	No	No

As nouns, being is a hypernym of possibleness; that is, being is a word with a broader meaning than possibleness:

Other hypernyms of possibleness include beingness, existence, face of the earth.

possibleness (noun)	being (noun)
capability of existing or happening or being true	a living thing that has (or can develop) the ability to act or function independently
	the state or fact of existing