ciated duration which is a special type of event. A duration is in a sense unbounded; for it is, within certain limitations, all that there is. It has the property of completeness, limited by the condition ‘now-present’; it is a temporal slab of nature.
16.2 This fact of nature as a present-whole is forced on our apprehension by the character of perception. Perceptual awareness is complex. There are the various types of sense-perception, and differences in extensity and in intensity. There are also differences in attention and in consequent clearness of awareness, shading off into a dim knowledge of events barely on the threshold of consciousness. Thus nature, as we know it, is a continuous stream of happening immediately present and partly dissected by our perceptual awareness into separated events with diverse qualities. Within this present stream the perceived is not sharply differentiated from the unperceived; there is always an indefinite ‘beyond’ of which we feel the presence although we do not discriminate the qualities of the parts. This knowledge of what is beyond discriminating perception is the basis of the scientific doctrine of externality. There is a present-whole of nature of which our detailed knowledge is dim and mediate and inferential, but capable of determination by its congruity with clear immediate perceptual facts.
16.3 The condition ‘now-present’ specifies a particular duration. It evidently refers to some relation; for ‘now’ is ‘simultaneous with,’ and ‘present’ is ‘in the presence of’ or ‘presented to.’ Thus ‘now-present’ refers to some relation between the duration and something else. This ‘something else’ is the event ‘here-present,’ which is the definite connecting link between
