to perception? Nothing less than the constitution of the being of perception in general, that is, its ontological nature, and similarly the constitution of the being of position. The ambiguous or the unclear use of the terms "perception" and "position" in Kant is the index of the fact that he leaves altogether undetermined the ontological nature of position and perception. This implies further that in the end the comportments of the ego, of the Dasein in our terminology, are ontologically undefined. The proper explicit ontology of the Dasein, of the being that we ourselves are, is in a bad way. But not only that; it also is not recognized that adequate treatment of the ontology of the Dasein is the presupposition for posing the problem whose solution Kant takes as his task in elucidating the concept of being.
At the outset here we shall not go into the fundamental concept of an ontology of the Dasein. This concept will occupy us in the second and third parts of the course. We shall refrain also from discussing its function as a foundation for philosophical inquiry in general; and still less is it possible to carry out and give an exposition of the ontology of the Dasein even in its main features. I have already offered an attempt at this in the first part of my recently published treatise Being and Time. Conversely, by continuing our analysis of the Kantian problem and the Kantian solution, we shall now try to make our way toward the sphere of the ontology of the Dasein as the foundation of ontology in general.
Kant interprets existence—we now say, in our terminology, extantness, because we reserve for the human being the term [ordinarily used by Kant for existence] "Dasein"—as perception. The threefold meaning, perceiving, perceived, perceivedness of the perceived, is to be kept in mind. But have we gained anything for the elucidation of the existence concept by taking explicit notice of the ambiguity of the expression "perception" and retaining the different meanings? Have we advanced any further in understanding the phenomenon intended by this expression when we differentiate the three meanings of the word "perception"? You surely do not gain any knowledge of a thing by enumerating what a word can mean in its ambiguity. Of course not. But these differences of meaning of the term "perception" have their ground ultimately in the thing signified by them, in the phenomenon of perception itself. Not only the differences of meaning as explicitly conscious, but also precisely the imprecise usage of the ambiguous word goes back perhaps to the peculiarity of the thing signified. Maybe this ambiguity of the expression "perception" is not accidental but bears witness exactly that the phenomenon intended by it already of itself gives to common experience and understanding the basis for interpreting it sometimes as perceiving, perceptual comportment, sometimes as the perceived in the sense of that to which perceptual comportment relates, sometimes as perceivedness in the sense of the being-perceived of what is perceived in