Nor is anything gained, as Aristotle supposes, by reminding the Herakleitean of his own practice in the daily concerns of life and in conversation with common persons: that he feeds himself with bread to-day, in the confidence that it has the same properties as it had yesterday;[70] that, if he wishes either to give or to obtain information, the speech which he utters or that which he acts upon must be either affirmative or negative. He will admit that he acts in this way, but he will tell you that he has no certainty of being right; that the negative may be true as well as the affirmative. He will grant that there is an inconsistency between such acts of detail and the principles of the Herakleitean doctrine, which recognize no real stability of any thing, but only perpetual flux or process; but inconsistency in detail will not induce him to set aside his principles. The truth is, that neither Herakleitus, nor Parmenides, nor Anaxagoras, nor Pythagoras, gave themselves much trouble to reconcile Philosophy with facts of detail. Each fastened upon some grand and impressive primary hypothesis, illustrated it by a few obvious facts in harmony therewith, and disregarded altogether the mass of contradictory facts. That a favourite hypothesis should contradict physical details, was noway shocking to them. Both the painful feeling accompanying that shock, and the disposition to test the value of the hypothesis by its consistency with inductive details, became first developed and attended to in the dialectical age, mainly through the working of Sokrates. The Analytic and the First Philosophy of Aristotle were constructed after the time of Sokrates, and with regard, in a very great degree, to the Sokratic tests and conditions — to the indispensable necessity for definite subjects and predicates, capable of standing the inductive scrutiny of particulars. In this respect the Philosophia Prima of Aristotle stands distinguished from that of any of the earlier philosophers, and even from that of Plato. He departed from Plato by recognizing the Hoc Aliquid or the definite Individual, with its essential Predicates, as the foundation of the Universal, and by applying his analytical factors of Form and Matter to the intellectual generation of the Individual (τὸ σύνολον — τὸ συναμφότερον); and thus he devised a First Philosophy conformable to the habits of common speech as rectified by the critical scrutiny of Sokrates. We shall see this in the next Chapter. * * * *

[70] Aristot. Metaph. K. vi. p. 1063, a. 31.

[The Author’s MS. breaks off here. What follows on the next page, as Chapter XII, is the exposition of Aristotle’s Psychology, originally contributed to the third edition of Professor Bain’s work ‘The Senses and the Intellect,’ in 1868.]

[CHAPTER XII.]

DE ANIMÂ, ETC.

To understand Aristotle’s Psychology, we must look at it in comparison with the views of other ancient Greek philosophers on the same subject, as far as our knowledge will permit. Of these ancient philosophers, none have been preserved to us except Plato, and to a certain extent Epikurus, reckoning the poem of Lucretius as a complement to the epistolary remnants of Epikurus himself. The predecessors of Aristotle (apart from Plato) are known only through small fragments from themselves, and imperfect notices by others; among which notices the best are from Aristotle himself.

In the Timæus of Plato we find Psychology, in a very large and comprehensive sense, identified with Kosmology. The Kosmos, a scheme of rotatory spheres, has both a soul and a body: of the two, the soul is the prior, grander, and predominant, though both of them are constructed or put together by the Divine Architect or Demiurgus. The kosmical soul, rooted at the centre, and stretched from thence through and around the whole, is endued with self-movement, and with the power of initiating movement in the kosmical body; moreover, being cognitive as well as motive, it includes in itself three ingredients mixed together:—(1) The Same — the indivisible and unchangeable essence of Ideas; (2) The Diverse — the Plural — the divisible bodies or elements; (3) A Compound, formed of both these ingredients melted into one. As the kosmical soul is intended to know all the three — Idem, Diversum, and Idem with Diversum in one, so it must comprise in its own nature all the three ingredients, according to the received Axiom — Like knows like — Like is known by Like. The ingredients are blended together according to a scale of harmonic proportion. The element Idem is placed in an even and undivided rotation of the outer or sidereal sphere of the Kosmos; the element Diversum is distributed among the rotations, all oblique, of the seven interior planetary spheres, that is, the five planets, with the Sun and Moon. Impressions of identity and diversity, derived either from the ideal and indivisible, or from the sensible and divisible, are thus circulated by the kosmical soul throughout its own entire range, yet without either voice or sound. Reason and Science are propagated by the circle of Idem: Sense and Opinion, by those of Diversum. When these last-mentioned circles are in right movement, the opinions circulated are true and trustworthy.[1]

[1] See this doctrine of the Timæus more fully expounded in ‘Plato and the Other Companions of Sokrates,’ III. xxxvi. [pp. 250-256], seq.

It is thus that Plato begins his Psychology with Kosmology: the Kosmos is in his view a divine immortal being or animal, composed of a spherical rotatory body and a rational soul, cognitive as well as motive. Among the tenants of this Kosmos are included, not only gods, who dwell in the peripheral or celestial regions, but also men, birds, quadrupeds, and fishes. These four inhabit the more central or lower regions of air, earth, and water. In describing men and the inferior animals, Plato takes his departure from the divine Kosmos, and proceeds downwards by successive stages of increasing degeneracy and corruption. The cranium of man was constructed as a little Kosmos, including in itself an immortal rational soul, composed of the same materials, though diluted and adulterated, as the kosmical soul; and moving with the like rotations, though disturbed and irregular, suited to a rational soul. This cranium, for wise purposes which Plato indicates, was elevated by the gods upon a tall body, with attached limbs for motion in different directions — forward, backward, upward, downward, to the right and left.[2] Within this body were included two inferior and mortal souls: one in the thoracic region near the heart, the other lower down, below the diaphragm, in the abdominal region; but both of them fastened or rooted in the spinal marrow or cord, which formed a continuous line with the brain above. These two souls were both emotional; the higher or thoracic soul being the seat of courage, energy, anger, &c., while to the lower or abdominal soul belonged appetite, desires, love of gain, &c. Both of them were intended as companions and adjuncts, yet in the relation of dependence and obedience, to the rational soul in the cranium above; which, though unavoidably debased and perturbed by such unworthy companionship, was protected partially against the contagion by the difference of location, the neck being built up as an isthmus of separation between the two. The thoracic soul, the seat of courage, was placed nearer to the head, in order that it might be the medium for transmitting influence from the cranial soul above, to the abdominal soul below; which last was at once the least worthy and the most difficult to control. The heart, being the initial point of the veins, received the orders and inspirations of the cranial soul, transmitting them onward through its many blood-channels to all the sensitive parts of the body; which were thus rendered obedient, as far as possible, to the authority of man’s rational nature.[3] The unity or communication of the three souls was kept up through the continuity of the cerebro-spinal column.