15.7 The fundamental rule is that events have parts and that—except in a derivative sense, from their relations to events—objects have no parts. On the other hand the same object can be found in different parts of space and time, and this cannot hold for events. Thus the identity of an object may be an important physical fact, while the identity of an event is essentially a trivial logical necessity. Thus the prisoner in the dock may be the man who did the deed. But the deed lies in the irrevocable past; only the allegation of it is before the court and perhaps (in some countries) a reconstitution of the crime. Essentially the very deed itself is never there. 15.8 The continuity of nature is to be found in events, the atomic properties of nature reside in objects. The continuous ether is the whole complex of events; and the atoms and molecules are scientific objects, which are entities of essentially different type to the events forming the ether. 15.9 This contrast in the ways we perceive events and objects deserves a distinction in nomenclature. Accordingly, for want of better terms, we shall say that we 'apprehend' an event and 'recognise' an object. To apprehend an event is to be aware of its passage as happening in that nature, which we each of us know as though it were common to all percipients. It is unnecessary for the purposes of science to consider the difficult metaphysical question of this community of nature to all. It is sufficient that, for the awareness of each, it is as though it were common to all, and that science is a body of doctrine true for this quasi-common nature which is the subject for the experience of each percipient; namely, science is true for each percipient. To recognise an object is to be aware of it in its specific relations to definite events in nature. Thus we refer the object to some events as its 'situations,' we connect it with other events as the locus from which it is being perceived, and we connect it with other events as conditions for such perception of it as in such situations from such a locus of percipience. Accordingly in these (arbitrary) senses of the words we apprehend nature as continuous and we recognise it as atomic. CHAPTER VI EVENTS 16. Apprehension of Events. 16.1 It is the purpose of this chapter to summarise the leading characteristics of our knowledge of nature as diversified into a complex of events.