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Rh ). The feeling of pleasure, e.g., is really only a motion in the heart, thought only a motion in the head. The psychology of Hobbes is therefore merely a part of his general theory of motion. His materialistic tendency which is apparent at this point is modified by his clear insight into the subjective conditions of knowledge. In a remarkable passage (De corpore, xxv, 1) he says: “The very fact that anything can become a phenomenon (id ipsum) (το φαινεσφαι) is indeed the most wonderful of all phenomena.” The fact that motion can be conceived, sensed, known, is therefore more wonderful than that it exists. The conception, the “apparition,” then cannot itself be motion, but must be an evidence that there is still something else in the universe besides motion.

Sensation, memory and comparison are intimately related to each other. If the sensory stimulus vanishes, instantly, there is in fact no sensation (sensio), but only a vague impression (phantasma). Real sensation presupposes a distinction and comparison of such impressions. The sensory stimuli must therefore vary, in order to make sensation possible.—Memories follow certain laws: they reappear in the same order of sequence as the original sensations, unless disarranged by the feelings and impulses. All order and every definite relation governing our ideas (except our temporal order of sequence) are conditioned by the fact that we are actuated by a purpose and seek the means for the realization of that purpose. The constant fixation of our purpose (frequens ad finem respectio) brings system into our thoughts. The capriciousness of dream-ideas is explained by the absence of a constant purpose during sleep.

He derives all individual feelings and volitional experiences from the impulse of self-preservation. Pleasure and