Medicine and philosophy - Classical Homeopathy Online

Heart, brain, blood, pneuma 129does not prevent him from repeatedly speaking of ‘experiences typical tothe soul’, activities a human being carries out ‘with his soul’, or perceptionswhich ‘penetrate the soul’. According to Aristotle, the functioning of thedual entity that body and soul constitute is governed by a large number oforgans and material factors. The heart is assigned the role of ‘beginning’ or‘origin’ (archē), both as a source of essential bodily heat (required amongother things for the digestion of food) and as the seat of the central senseorgan, which is connected with the limbs and the separate sense organs andco-ordinates the data it receives from them. 21 Furthermore, in exercisingthis co-ordinating task the heart is supported by the blood (as a mediumfor transporting sensory information) and air (pneuma, for the transmissionof motor signals). Their role is important, yet not fully defined. 22 Thesize of the heart, which differs in each species of animal, has an influenceon certain character traits and on susceptibility to certain emotions; 23 thecondition of the blood (pure, turbid, cold, hot) influences the quality andspeed of sense perception. 24 The brain is not involved in all this: it has nocognitive faculties and serves only as a chilling element in the body, fortempering the heat that radiates from the heart. 25An even more elaborate physiological theory is presented by Diocles ofCarystus (fourth century bce). He assumes interaction between the heart(to him the real seat of the mind), the brain (which plays a pivotal role insense perception) and the so-called ‘psychic pneuma’, a delicate substancethat is responsible for transmitting sensory and motor signals. 26It is clear, then, that many medical authors of the fifth and fourth centuriesbce assume a cognitive centre somewhere in the body from whereabilities such as perception and movement are ‘transported’ or ‘transferred’to peripheral organs. Organs for perception, limbs and other parts of thebody are assumed to be connected to each other and to a centre via certain‘passages’ (poroi, phlebes, neura). 27 Through these passages air or bloodare conducted; an accumulation of certain bodily fluids (such as phlegmor bile) can cause the passages to get blocked. The assumption of theexistence of this network of passages and the ideas about their course andramifications are highly speculative and hardly based on what we would21 On Youth and Old Age (De iuventute et senectute, De iuv.) 468 b 32ff.22 There is much debate on the question whether it is the blood or pneuma which, according toAristotle, carries sensory information in the body. A summary and standpoint can be found in vander Eijk (1994) 81–7.23 Part. an. 667 a 10–20. 24 Part. an. 656 b 5; 648 a 2ff.; 650 b 19ff.25 Part. an. 2.7. 26 Diocles, frs. 78 and 80 vdE.27 In this respect it should be noted that nerves were not discovered until after Aristotle, in third-centuryAlexandria.