The sense-data are ‘given’ for presentational immediacy. This given-ness of the sense-data, as the basis of this perceptive mode, is the great doctrine common to Hume and Kant. But what is already given for experience can only be derived from that natural potentiality which shapes a particular experience in the guise of causal efficacy. Causal efficacy is the hand of the settled past in the formation of the present. The sense-data must therefore play a double rôle in perception. In the mode of presentational immediacy they are projected to exhibit the contemporary world in its spatial relations. In the mode of causal efficacy they exhibit the almost instantaneously precedent bodily organs as imposing their characters on the experience in question. We see the picture, and we see it with our eyes; we touch the wood, and we touch it with cur hands; we smell the rose, and we smell it with our nose; we hear the bell, and we hear it with our ears; we taste the sugar, and we taste it with our palate. In the case of bodily feelings the two locations are identical. The foot is both giving pain and is the seat of the pain. Hume himself tacitly asserts this double reference in the second of the quotations previously made. He writes: “If it be perceived by the eyes, it must
