1. One does not start with the idea that existence is material, spiritual or any other "fact."
2. Compositional fallacy.
3. While Objectivism is a philosophy of realism the idea of "enties," "properties," "attributes" etc [as traditional realism would have it] are just changes in our level of perception and have no "intrinsic nature." Existence exists, it exists some way and has primacy. An entity is that "part" which is focused upon now - the properties and attributes it has are things it has now. Later, we might change our focus regarding that "entity" and consider the "property" as an entity. [An orthodox objectivist may have a problem with this view.]
What is necessary is existence and it existing some way - what is contingent is are our "conceptions" of it.
