Plotinos: Complete Works, v. 4 / In Chronological Order, Grouped in Four Periods

by Plotinus

Aristo (there were two philosophers by this name, one a Stoic, the other an Aristotelian) attributes to the soul a perceptive faculty, which he divides into two parts. According to him, the first, called sensibility, the principle and origin of sensations, is usually kept active by some one of the sense-organs. The other, which subsists by itself, and without organs, does not bear any special name in beings devoid of reason, in whom reason does not manifest, or at least manifests only in a feeble or obscure manner; however, it is called intelligence in beings endowed with reason, among whom alone it manifests clearly. Aristo holds that sensibility acts only with the help of the sense-organs, and that intelligence does not need them to enter into activity. Why then does he subordinate both of these to a single genus, called the perceptive faculty? Both doubtless perceive, but the one perceives the sense-form of beings, while the other perceives their essence. Indeed, sensibility does not perceive the essence, but the sense-form, and the figure; it is intelligence that perceives whether the object be a man or a horse. There are, therefore, two kinds of perception that are very different from each other; sense-perception receives an impression, and applies itself to an exterior object; on the contrary, intellectual perception does not receive any impression.

There have been philosophers who separated these two parts; they called intelligence or discursive reason the understanding which is exercised without imagination and sensation; and opinion, the understanding which is exercised with imagination and sensation. Others, on the contrary, considered rational "being," or nature, a simple essence, and attributed to it operations whose nature is entirely different. Now it is unreasonable to refer to the same essence faculties which differ completely in nature; for thought and sensation could not depend on the same essential principle; and if we were to call the operation of intelligence a perception, we would only be juggling with words. We must, therefore, establish a perfectly clear distinction between these two entities, intelligence and sensibility. On the one hand, intelligence possesses a quite peculiar nature, as is also the case with discursive reason, which is next below it. The function of the former is intuitive thought, while that of the latter is discursive thought. On the other hand, sensibility differs entirely from intelligence, acting with or without the help of organs; in the former case, it is called sensation; in the latter, imagination. Nevertheless, sensation and imagination belong to the same genus. In understanding, intuitive intelligence is superior to opinion, which applies to sensation or imagination; this latter kind of thought, whether called discursive thought, or anything else (such as opinion), is superior to sensation and imagination, but inferior to intuitive thought.

OF ASSENT.

Numenius, who teaches that the faculty of assent (or, combining faculty) is capable of producing various operations, says that representation (fancy) is an accessory of this faculty, that it does not, however, constitute either an operation or function of it, but a consequence of it. The Stoics, on the contrary, not only make sensation consist in representation, but even reduce representation to (combining) assent. According to them sense-imagination (or sense-fancy) is assent, or the sensation of the determination of assent. Longinus, however, does not acknowledge any faculty of assent. The philosophers of the ancient Academy (the Platonists) believe that sensation does not comprise sense-representation, and that, consequently, it does not have any original property, since it does not participate in assent. If sense representation consisted of assent added to sensation, sensation, by itself, will have no virtue, since it is not the assent given to the things we possess.

OF THE PARTS OF THE SOUL.

It is not only about the faculties that the ancient philosophers disagree.... They are besides in radical disagreement about the following questions: What are the parts of the soul; what is a part; what is a faculty; what difference is there between a part and a faculty?

The Stoics divide the soul into eight parts: the five senses, speech, sex-power, and the directing (predominating) principle, which is served by the other faculties, so that the soul is composed of a faculty that commands, and faculties that obey.

In their writing about ethics, Plato and Aristotle divide the soul into three parts. This division has been adopted by the greater part of later philosophers; but these have not understood that the object of this definition was to classify and define the virtues (Plato: reason, anger and appetite; Aristotle: locomotion, appetite and understanding). Indeed, if this classification be carefully scrutinized, it will be seen that it fails to account for all the faculties of the soul; it neglects imagination, sensibility, intelligence, and the natural faculties (the generative and nutritive powers).

Other philosophers, such as Numenius, do not teach one soul in three parts, like the preceding, nor in two, such as the rational and irrational parts. They believe that we have two souls, one rational, the other irrational. Some among them attribute immortality to both of the souls; others attribute it only to the rational soul, and think that death not only suspends the exercise of the faculties that belong to the irrational soul, but even dissolves its "being" or essence. Last, there are some that believe, that by virtue of the union of the two souls, their movements are double, because each of them feels the passions of the other.