It seems to be an obvious truth that
(1) There could be something that doesn't actually exist.
That is, it seems to be obiously true that
(1a) ◊∃×(Actually ∼ (× exists)).
It is sufficient for the truth of (1) that there could be more people, or trees, or cars, than there actually are. It is also sufficient for the truth of (1) that there could be some pepole, or trees, or cars that are distinct from all those that actually exist. Do (1) and suchlike statements involve a commitment to possibilia, to things that possibly exist, but do not actually exist? If not, why not? And if so, what is the nature of the possibilia to which (1) and its ilk commit us? These simple little questions are at the tip of an iceberg.