The clause 'furthermore are worldless' must not be left out; for even entities which are not worldless—Dasein itself, for example—are present-at-hand 'in' the world, or, more exactly, can with some right and within certain limits be taken as merely present-at-hand. To do this, one must completely disregard or just not see the existential state of Being-in. But the fact that 'Dasein' can be taken as something which is present-at-hand and just present-at-hand, is not to be confused with a certain way of 'presence-at-hand' which is Dasein's own. This latter kind of presence-at-hand becomes accessible not by disregarding Dasein's specific structures but only by understanding them in advance. Dasein understands its ownmost Being in the sense of a certain  'factual Being-present-at-hand'.ii And yet the 'factuality' of the fact [Tatsache] of one's own Dasein is at bottom quite different ontologically from the factual occurrence of some kind of mineral, for example. Whenever Dasein is, it is as a Fact; and the factuality of such a Fact is what we shall call Dasein's "facticity".1 This is a definite way of Being [Seinsbestimmtheit], and it has a complicated structure which cannot even be grasped as a problem until Dasein's basic existential states have been worked out. The concept of "facticity" implies that an entity 'within-the-world' has Being-in-the-world in such a way that it can understand itself as bound up in its 'destiny' with the Being of those entities which it encounters within its own world.
In the first instance it is enough to see the ontological difference between Being-in as an existentiale and the category of the 'insideness' which things present-at-hand can have with regard to one another. By thus delimiting Being-in, we are not denying every kind of 'spatiality' to Dasein. On the contrary, Dasein itself has a 'Being-in-space' of its own; but this in turn is possible only on the basis of Being-in-the-world in general . Hence Being-in is not to be explained ontologically by some ontical characterization, as if one were to say, for instance, that Being-in in a world is a spiritual property, and that man's 'spatiality' is a result of his bodily nature (which, at the same time, always gets 'founded' upon corporeality). Here again we are faced with the Being-present-at-hand-together of some such spiritual Thing along with a corporeal Thing, while the Being of the entity thus compounded remains more obscure than ever.
1 'Die Tatsachlichkeit des Faktums Dasein, als welches jeweilig jedes Dasein ist, nennen wir seine Faktizität.' We shall as a rule translate 'Tatsächlichkeit' as 'factuality', and 'Faktizität' as 'facticity', following our conventions for 'tatsächlich' and 'faktisch'. (See note 2, p. 27, H. 7 above.) The present passage suggests a comparable distinction between the nouns 'Tatsache' and 'Faktum'; so while we find many passages where these seem to be used interchangeably, we translate 'Faktum' as 'Fact' with an initial capital, using 'fact' for 'Tatsache' and various other expressions. On 'factuality' and 'facticity' see also H. 135 below.