Process and Reality — the Gifford Lectures, 1929

nervous strand, and so on. The total association of the sense-datum with space-time is analysable into a bewildering variety of associations with definite regions, contemporary and antecedent. In general, and apart from high-grade organisms, this spatio-temporal association of the sense-datum is integrated into a vague sense of externality. The component valuations have in such cases failed to differentiate themselves into grades of intensity. But in high grade cases, in which presentational immediacy is prominent, one of three cases happens. Either (i) the association of the sense-datum with the seats of some antecedent sets of feelers is exclusively emphasized, or (ii) the association of the sense-datum with the focal region of the final percipient is exclusively emphasized, or (ili) the association of the sense-datum both with the seats of antecedent feelers and with the focal region of the immediate feeler is emphasized.

But these regions are not apprehended in abstraction from the general spatio-temporal continuum. The prehension of a region is always the prehension of systematic elements in the extensive relationship between the seat of the immediate feeler and the region concerned. When these valuations have been effected, the category of transmutation provides for the transmission to the succeeding subject of a feeling of these regions qualified by (i.e. contrasted with) that sense-datum. In the first case, there are purely bodily sensations; in the second case there are ‘projected’ sensations, involving regions of contemporary space beyond the body; in the third case there are both bodily feelings and sensations externally projected. Thus in the case of all sensory feeling, there is initial privacy of conceptual emphasis passing into publicity of physical feeling.

Thus, by the agency of the category of transmutation, there are two types of feelings, for which the objective datum is a nexus with undiscriminated actual entities. The feelings of the first type are feelings of ‘causal efficacy’; and those of the second type are those of ‘presentap. 479tional immediacy.’ In the first type the analogous elements in the various feelings of the various actualities of the bodily nexus are transmuted into a feeling ascribed to the bodily nexus as one entity. In the second type, the transmutation is more elaborate and shifts the nexus concerned from the antecedent bodily nexus (ie. the ‘seat’) to the contemporary focal nexus.

Both these types of feeling are the outcome of a complex process of massive simplification which is characteristic of higher grades of actual entities. They apparently have but slight importance in the constitutions of actual occasions in empty space; but they have dominating importance in the physical feelings belonging to the life history of enduring organisms—the inorganic and organic, alike.

In respect to the sensa concerned, there is a gradual transformation of their functions as they pass from occasion to occasion along a route of inheritance up to some final high-grade experient. In their most primitive form of functioning, a sensum is felt physically with emotional enjoyment of its sheer individual essence. For example, red is felt with emotional enjoyment of its sheer redness. In this primitive prehension we have aboriginal physical feeling in which the subject feels itself as enjoying redness. This is Hume’s ‘impression of sensation’ stripped of all spatial relations with other such impressions. In so far as they spring up in this primitive, aboriginal way, they—in Hume’s words—“arise in the soul from unknown causes.” But in fact we can never isolate such ultimate irrationalities. In our experience, as in distinct analysis, physical feelings are always derived from some antecedent experient. Occasion B prehends occasion A as an antecedent subject experiencing a sensum with emotional intensity. Also B’s subjective form of emotion is conformed to A’s subjective form. Thus there is a vector transmission of emotional feeling of asensum from A to B. In this way B feels the sensum as derived from A and feels it with an emotional formp. 480 also derived from A. This is the most primitive form of the feeling of causal efficacy. In physics it is the transmission of a form of energy. In the bodily transmission from occasion to occasion of a high-grade animal body, there is a gradual modification of these functions of sensa. In their most primitive functioning for the initial occasions within the animal body, they are qualifications of emotion—types of energy, in the language of physics: in their final functioning for the high-grade experient occasion at the end of the route, they are qualities ‘inherent’ in a presented, contemporary nexus. In the final percipient any conscious feeling of the primitive emotional functioning of the sensum is often entirely absent. But this is not always the case; for example, the perception of a red cloak may often be associated with a feeling of red irritation.

To return to Hume’s doctrine (cf. Treatise, Part III, Sect. V) of the origination of ‘impressions of sensation’ from unknown causes, it is first necessary to distinguish logical priority from physical priority. Undoubtedly an impression of sensation is logically the simplest of physical prehensions. It is the percipient occasion feeling the sensum as participating in its own concrescence. This is the enjoyment of a private sensation.

There is a logical simplicity about such a sensation which makes it the primitive, aboriginal type of physical feeling. But there are two objections to Hume’s doctrine which assigns to them a physical priority. First, there is the empirical objection. Hume’s theory of a complex of such impressions elaborated into a supposition of a common physical world is entirely contrary to naive experience. We find ourselves in the double role of agents and patients in a common world, and the conscious recognition of impressions of sensation is the work of sophisticated elaboration. This is also Locke’s doctrine in the third and fourth books of his Hssay. The child first dimly elucidates the complex externality of particup. 481lar things exhibiting a welter of forms of definiteness, and then disentangles his impressions of these forms in isolation. A young man does not initiate his experience by dancing with impressions of sensation, and then proceed to conjecture a partner. His experience takes the converse route. The unempirical character of the philosophical school derived from Hume cannot be too often insisted upon. The true empirical doctrine is that physical feelings are in their origin vectors, and that the genetic process of concrescence introduces the elements which emphasize privacy.

Secondly, Hume’s doctrine is necessarily irrational. For if the impressions of sensation arise from unknown causes (ef. Hume, loc. cit.) a stop is put to the rationalistic search for a rational cosmology. Such a cosmology requires that metaphysics shall provide a doctrine of relevance between a form and any occasion in which it participates. If there be no such doctrine, all hope of approximating to a rational view of the world vanishes.

Hume’s doctrine has no recommendation except the pleasure which it gives to its adherents.