One of the most important theses of Existential Thomism is that contingent things are composed of essence and existence. The thesis is immediately supplemented by a proviso that these components are not parts in the regular sense of the word. Essence and existence are not extended pieces of the thing which can be detached from it. They are inseparable aspects of the thing wherein inseparability is understood as a sort of dependence. In my paper I analyze the thesis of the (...) inseparability of existence. For me this is untenable. I argue that this inseparability blocks up the essential function ascribed by Thomists to existence: the function of making the thing real. Thus to save this function we are forced to export existence to outside the thing. It contradicts our deep belief that existence is the most intimate aspect of the thing. Therefore the Thomistic analysis of existence seems to be invalid. (shrink)