possibility of its 'failure to stand by itself'1 requires that we formulate the question existentially and ontologically as the sole appropriate way of access to its problematic.
But if the Self is conceived 'only' as a way of Being of this entity, this seems tantamount to volatilizing the real 'core' of Dasein. Any apprehensiveness however which one may have about this gets its nourishment from the perverse assumption that the entity in question has at bottom the kind of Being which belongs to something present-at-hand, even if one is far from attributing to it the solidity of an occurrent corporeal Thing. Yet man's 'substance' is not spirit as a synthesis of soul and body; it is rather existence.
¶ 26. The Dasein-with of Others and Everyday Being-with
The answer to the question of the "who" of everyday Dasein is to be obtained by analysing that kind of Being in which Dasein maintains itself proximally and for the most part. Our investigation takes its orientation from Being-in-the-world—that basic state of Dasein by which every mode of its Being gets co-determined. If we are correct in saying that by the foregoing explication of the world, the remaining structural items of Being-in-the-world have become visible, then this must also have prepared us, in a way, for answering the question of the "who".
In our 'description' of that environment which is closest to us—the work-world of the craftsman, for example,—the outcome was that along with the equipment to be found when one is at work [in Arbeit], those Others for whom the 'work' ["Werk"] is destined are 'encountered too'.2 If this is ready-to-hand, then there lies in the kind of Being which belongs to it (that is, in its involvement) an essential assignment or reference to possible wearers, for instance, for whom it should be 'cut to the figure'. Similarly, when material is put to use, we encounter its producer or 'supplier' as one who 'serves' well or badly. When, for example, we walk along the edge of a field but 'outside it', the field shows itself as belonging [118] to such-and-such a person, and decently kept up by him; the book we have used was bought at So-and-so's shop and given by such-and-such
1 '... die Ständigkeit des Selbst ebensosehr wie seine mögliche "Unselbständigkeit" ...' The adjective 'ständig', which we have usually translated as 'constant' in the sense of 'permanent' or 'continuing', goes back to the root meaning of 'standing', as do the adjectives 'selbständig" ('independent') and 'unselbständig' ('dependent'). These concepts will be discussed more fully in Section 64 below, especially H. 322, where 'Unselbständigkeit' will be rewritten not as 'Un-selbständkeit' ('failure to stand by one's Self') but as 'Unselbst-ständigkeit' ('constancy to the Unself'). See also H. 128. (The connection with the concept of existence will perhaps be clearer if one recalls that the Latin verb 'existere' may also be derived from a verb of standing, as Heidegger points out in his later writings.)
2 Cf. Section 15 above, especially H. 70f.