In grasping the entity in terms of a certain sort of possibility, I am making it meaningful as a certain sort of what (essentia). A particular kind of that (existentia) will correspond to this. In other words: for different kinds of entities there are different kinds of standards for counting as that and what they are. What the teacup is is what it is for (in order to), since tools are meaningful in terms of what they are correctly used for. The fact that the teacup is consists in its being available for use: it is the case that there is a teacup when there is an entity that it is possible to use in the way that teacups are used. A piece of quartz, by contrast, will have its that-being in manifesting a certain chemical composition. Its being what it is consists in that chemical composition falling within a range of possible patterns of oxygen, silicon, and other atoms. These examples show that there is a variety of kinds of that- and what-beings—what we might call different “ways” or “ modes ” of being. There is thus a variety of ways in which entities can make sense, and correspondingly different “categories of intelligibility.” Since not everything is meaningful in the same way, we (like Aristotle) must conclude that being is said in many ways. Heidegger is thus an ontological pluralist.
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