Alfred North Whitehead, answered from the texts and cited to the page.
Concrescence is the name for the process by which the universe of many things acquires individual unity — the advance from disjunction to conjunction in which a novel entity comes to be.1 Let me say what that means with some precision. Every actual occasion finds itself in a world already there: a multiplicity of completed occasions, each determinate, each having perished into the past.
The concrescing occasion does not merely receive these as inert data; it feels them, appropriates them, integrates them into a new unity through what I call prehension — the elementary act of feeling by which one occasion takes up another into its own becoming.2 The diverse feelings that arise in this process pass on to wider generalities of integral feeling, until the occasion achieves its own determinate character, its satisfaction.3
What is crucial — and what the term itself is meant to convey — is that concrescence is not the assembly of pre-existing parts into a container. When we analyse the novel thing, we find nothing but the concrescence itself; there are not "the concrescence" and "the novel thing" as two separate items.4 The actuality just is this ultimate entry into the concrete.
To abstract from it entirely is self-contradictory, since it asks us to conceive a thing as not a thing.5 The term carries the Latin root deliberately: concrescere, to grow together. Many things acquire complex unity.6 But I chose the word with a reservation: it fails, taken alone, to suggest the creative novelty involved, the individual character — the subjective form, the emotionalized quality — that arises in each instance and is irreducible to the aboriginal data.7
This is why the full vocabulary requires several words correcting one another: together, creativity, concrescence, prehension, feeling, subjective form, data, actuality, becoming, process.8 The metaphysical principle at work here replaces Aristotle's category of primary substance. Where substance metaphysics posits an enduring thing that possesses attributes, the philosophy of organism posits this: the many become one, and are increased by one.9
The novel occasion is at once the togetherness of the many it finds and also one among the disjunctive many it leaves behind — a new member of the universe it has synthesized.10 And because creativity admits no final resting point, any completed set of actual occasions becomes in turn the datum for a further concrescence; the actual world is always a relative term, always the presupposed basis for a new becoming.11
Furthermore — and this is what Science and the Modern World presses — there are no isolated occasions. Actuality is through and through togetherness: every occasion is a synthesis of all occasions under the limitation of gradations of types of entry, just as it is a synthesis of all eternal objects under gradations of actuality.12 Each occasion synthesises the totality of content under its own limitations of mode.13
Concrescence is therefore not a local event sealed off from the rest; it is the universe gathering itself into a new particular, and that particular then perishing into objective immortality for the occasions that follow.
'Concrescence' is the name for the process in which the universe of many things acquires an individual unity in a determinate relegation of each item of the 'many' to its subordination in the constitution of the novel 'one.'Process and Reality, p. 237
An actual occasion is a concrescence effected by a process of feelings. A feeling can be considered in respect to (i) the actual occasions felt, (ii) the eternal objects felt, (iii) the feelings felt, and (iv) its own subjective forms of intensity.Process and Reality, p. 237
In the process of concrescence the diverse feelings pass on to wider generalities of integral feeling.Process and Reality, p. 237
There are not 'the concrescence' and 'the novel thing': when we analyse the novel thing we find nothing but the concrescence.Process and Reality, p. 237
'Actuality' means nothing else than this ultimate entry into the concrete, in abstraction from which there is mere nonentity. In other words, abstraction from the notion of 'entry into the concrete' is a self-contradictory notion, since it asks us to conceive a thing as not a thing.Process and Reality, p. 237
Concrescence is useful to convey the notion of many things acquiring complete complex unity.Adventures of Ideas, pp. 319–321
But it fails to suggest the creative novelty involved. For example, it omits the notion of the individual character arising in the concrescence of the aboriginal data. The event is not suggested as 'emotionalized', that is, as with its 'subjective form'.Adventures of Ideas, pp. 319–321
We require 'together', 'creativity', 'concrescence', 'prehension', 'feeling', 'subjective form', 'data', 'actuality', 'becoming', 'process'.Adventures of Ideas, pp. 319–321
The many become one, and are increased by one. In their natures, entities are disjunctively 'many' in process of passage into conjunctive unity. This Category of the Ultimate replaces Aristotle's category of 'primary substance.'Process and Reality, pp. 48–49
The novel entity is at once the togetherness of the 'many' which it finds, and also it is one among the disjunctive 'many' which it leaves; it is a novel entity, disjunctively among the many entities which it synthesizes.Process and Reality, pp. 48–49
Thus a set of all actual occasions is by the nature of things a standpoint for another concrescence which elicits a concrete unity from those many actual occasions... Thus we can never survey the actual world except from the standpoint of an immediate concrescence which is falsifying the presupposed completion.Process and Reality, p. 237
Actuality is through and through togetherness... so every occasion is a synthesis of all occasions under the limitation of gradations of types of entry.Science and the Modern World, p. 14
Each occasion synthesises the totality of content under its own limitations of mode.Science and the Modern World, p. 14