15.2 The change of an object is the diverse relationships of the same object to diverse events. The object is permanent, because (strictly speaking) it is without time and space; and its change is merely the variety of its relations to the various events which are passing in time and in space. This passage of events in time and space is merely the exhibition of the relations of extension which events bear to each other, combined with the directional factor in time which expresses that ultimate becomingness which is the creative advance of nature. These extensional relations of events are analysed in later parts of this enquiry. But here we merely make clear that change in objects is no derogation from their permanence, and expresses their relation to the passage of events; whereas events are neither permanent nor do they change. Events (in a sense) are space and time, namely, space and time are abstractions from events. But objects are only derivatively in space and time by reason of their relations to events. 15.3 The ways in which events and objects enter into experience are distinct. Events are lived through, they extend around us. They are the medium within which our physical experience develops, or, rather, they are themselves the development of that experience. The facts of life are the events of life. Objects enter into experience by way of the intellectuality of recognition. This does not mean that every object must have been known before; for in that case there never could have been a first knowledge. We must rid our imagination of the fallacious concept of the present as instantaneous. It is a duration, or stretch of time; and the primary recognition of an object consists of the recognition of its permanence amid the partial events of the duration which is present. Its recognition is carried beyond the present by means of recollection and memory. Rational thought which is the comparison of event with event would be intrinsically impossible without objects. 15.4 Objects and events are only waveringly discriminated in common thought. Whatever is purely matter of fact is an event. Whenever the concept of possibility can apply to a natural element, that element is an object. Namely, objects have the possibility of recurrence in experience: we can conceive imaginary circumstances in which a real object might occur. The essence of an object does not depend on its relations, which are external to its being. It has in fact certain relations to other natural elements; but it might (being the same object) have had other relations. In other words, its self-identity is not wholly dependent on its relations. But an event is just what it is, and is just how it is related; and it is nothing else.