Roman Stoicism / being lectures on the history of the Stoic philosophy with special reference to its development within the Roman Empire

by Edward Vernon Arnold

The five senses.

276. The nature of sensation is more particularly described in the case of sight and hearing. In the first case there proceed from the eyes rays, which cause tension in the air, reaching towards the object seen[68]; this tension is cone-shaped, and as the distance from the pupil of the eye increases, the base of the cone is increased in size, whilst the vigour of the sight diminishes. This human activity effects vision of itself in one case; for we say ‘darkness is visible,’ when the eye shoots forth light at it, and correctly recognises that it is darkness[69]. But in complete vision there is an opposing wave-motion coming from the object, and the two waves become mutually absorbed: hence Posidonius called sight ‘absorption’ (σύμφυσις)[70]. Similarly, in the case of hearing, the pulsation (which, as we have seen, comes in the first instance from the principate) spreads from the ear to the speaker, and (as is now more distinctly specified) from the speaker to the hearer; this reverse pulsation being circular in shape, like the waves excited on the surface of a lake by throwing a stone into the water[71]. Of the sensations of smell, taste and touch we only hear that they are respectively (i) a spirit extending from the principate to the nostrils, (ii) a spirit extending from the principate to the tongue, and (iii) a spirit extending to the surface of the body and resulting in the easily-appreciated touch of an object[72].

Other activities.

277. The Stoic account of the functions of the soul displayed in the ordinary activities of life is either defective or mutilated; for even a slight outline of the subject should surely include at least breathing, eating (with drinking), speech, walking, and lifting. We need not however doubt that these, equally with the five senses, are all ‘spirits stretching from the principate’ to the bodily organs. This is expressly stated of walking[73]. Of all such activities we must consider voice to be typical, when it is described as the sixth function of the soul. Voice is described as ‘pulsating air[74],’ set in motion by the tongue[75]; but we can trace it back through the throat to some source below, which we can without difficulty identify with the heart, the seat of the principate[76]. The voice is indeed in a special relationship to the principate, since the spoken word is but another aspect of the thought which is expressed by it[77].

Procreation.

278. The seventh and last of the subordinate powers of the soul, according to the Stoics, is that of procreation. This part of their system is of great importance, not only for the study of human nature, but even in a higher degree for its indirect bearing upon the question of the development of the universe through ‘procreative principles’ (σπερματικοὶ λόγοι), or, as we have termed them above, ‘seed powers[78].’ That all things grow after their kind is of course matter of common knowledge; no combination of circumstances, no scientific arrangement of sustenance can make of an acorn anything but an oak, or of a hen’s egg anything but a chicken. But in the common view this is, at least primarily, a corporeal or material process; whereas the Stoics assert that it is not only a property of the soul, but one so primary and fundamental that it must be also assumed as a first principle of physical science. Before approaching the subject from the Stoic standpoint, it may be well to see how far materialistic theories, ancient and modern, can carry us.

Heredity.

279. Lucretius finds this a very simple matter:

‘Children often resemble not only their parents, but also their grandparents and more remote ancestors. The explanation is that the parents contain in their bodies a large number of atoms, which they have received from their ancestors and pass on to their descendants. In the chance clashing of atoms in procreation Venus produces all kinds of effects, bringing about resemblances between children and their forebears, not only in the face and person, but also in the look, the voice, and the hair[79].’

This account has a generally plausible sound until we bear in mind that it is the fundamental property of atoms that, though their own variety is limited, they can form things in infinite variety by changes in their combination and arrangement. They are like the letters out of which words, sentences, and poems are made up; and we can hardly expect to reproduce the voice or the spirit of an Aeschylus by a fresh shuffling of the letters contained in the Agamemnon. On the contrary, seeing that the atoms contained in the bodies of parents have largely been drawn from plants and animals, we could confidently reckon upon finding the complete fauna and flora of the neighbourhood amongst their offspring. Lucretius in effect postulates in his theory that particular atoms have a representative and creative character, passing from father to child in inseparable association with the marks of the human race, and endowed with a special capacity of combining with other like atoms to form the substratum of specifically human features. In giving his atoms these properties he is insensibly approximating to the Stoic standpoint.