Abstract
This paper tries to understand existence as identified with Aquinas' esse in a right way. The author distinguishes among facticity and existence, because facticity it a mere negative understanding of existence as the negation of nothing. But existence is not only a negative thing, but a positive one, therefore it is not still described by this negative definition. Existence includes facticity but is not only facticity. Existence is the actuality of essence and that description does not diminish Aquinas' understanding of esse but puts it in its true dimension.