(28) Thus much established, we may return on our path: we have to discuss the seat of the passionate element in the human being.

Pleasures and pains- the conditions, that is, not the perception of them- and the nascent stage of desire, we assigned to the body as a determined thing, the body brought, in some sense, to life: are we entitled to say the same of the nascent stage of passion? Are we to consider passion in all its forms as vested in the determined body or in something belonging to it, for instance in the heart or the bile necessarily taking condition within a body not dead? Or are we to think that just as that which bestows the vestige of the soul is a distinct entity, so we may reason in this case- the passionate element being one distinct thing, itself, and not deriving from any passionate or percipient faculty?

Now in the first case the soul-principle involved, the vegetal, pervades the entire body, so that pain and pleasure and nascent desire for the satisfaction of need are present all over it- there is possibly some doubt as to the sexual impulse, which, however, it may suffice to assign to the organs by which it is executed- but in general the region about the liver may be taken to be the starting point of desire, since it is the main acting point of the vegetal principle which transmits the vestige phase of the soul to the liver and body- the seat, because the spring.

But in this other case, of passion, we have to settle what it is, what form of soul it represents: does it act by communicating a lower phase of itself to the regions round the heart, or is it set in motion by the higher soul-phase impinging upon the Conjoint , or is there, in such conditions no question of soul-phase, but simply passion itself producing the act or state of anger?

Evidently the first point for enquiry is what passion is.

Now we all know that we feel anger not only over our own bodily suffering, but also over the conduct of others, as when some of our associates act against our right and due, and in general over any unseemly conduct. It is at once evident that anger implies some subject capable of sensation and of judgement: and this consideration suffices to show that the vegetal nature is not its source, that we must look for its origin elsewhere.

On the other hand, anger follows closely upon bodily states; people in whom the blood and the bile are intensely active are as quick to anger as those of cool blood and no bile are slow; animals grow angry though they pay attention to no outside combinations except where they recognize physical danger; all this forces us again to place the seat of anger in the strictly corporeal element, the principle by which the animal organism is held together. Similarly, that anger or its first stirring depends upon the condition of the body follows from the consideration that the same people are more irritable ill than well, fasting than after food: it would seem that the bile and the blood, acting as vehicles of life, produce these emotions.

Our conclusion will identify, first, some suffering in the body answered by a movement in the blood or in the bile: sensation ensues and the soul, brought by means of the representative faculty to partake in the condition of the affected body, is directed towards the cause of the pain: the reasoning soul, in turn, from its place above the phase not inbound with body-acts in its own mode when the breach of order has become manifest to it: it calls in the alliance of that ready passionate faculty which is the natural combatant of the evil disclosed.

Thus anger has two phases; there is firstly that which, rising apart from all process of reasoning, draws reason to itself by the medium of the imaging faculty, and secondly that which, rising in reason, touches finally upon the specific principle of the emotion. Both these depend upon the existence of that principle of vegetal life and generation by which the body becomes an organism aware of pleasure and pain: this principle it was that made the body a thing of bile and bitterness, and thus it leads the indwelling soul-phase to corresponding states- churlish and angry under stress of environment- so that being wronged itself, it tries, as we may put it, to return the wrong upon its surroundings, and bring them to the same condition.

That this soul-vestige, which determines the movements of passion is of one essence with the other is evident from the consideration that those of us less avid of corporeal pleasures, especially those that wholly repudiate the body, are the least prone to anger and to all experiences not rising from reason.

That this vegetal principle, underlying anger, should be present in trees and yet passion be lacking in them cannot surprise us since they are not subject to the movements of blood and bile. If the occasions of anger presented themselves where there is no power of sensation there could be no more than a physical ebullition with something approaching to resentment ; where sensation exists there is at once something more; the recognition of wrong and of the necessary defence carries with it the intentional act.

But the division of the unreasoning phase of the soul into a desiring faculty and a passionate faculty- the first identical with the vegetal principle, the second being a lower phase of it acting upon the blood or bile or upon the entire living organism- such a division would not give us a true opposition, for the two would stand in the relation of earlier phase to derivative.

This difficulty is reasonably met by considering that both faculties are derivatives and making the division apply to them in so far as they are new productions from a common source; for the division applies to movements of desire as such, not to the essence from which they rise.

That essence is not, of its own nature, desire; it is, however, the force which by consolidating itself with the active manifestation proceeding from it makes the desire a completed thing. And that derivative which culminates in passion may not unreasonably be thought of as a vestige-phase lodged about the heart, since the heart is not the seat of the soul, but merely the centre to that portion of the blood which is concerned in the movements of passion.

(23) I explain: A living body is illuminated by soul: each organ and member participates in soul after some manner peculiar to itself; the organ is adapted to a certain function, and this fitness is the vehicle of the soul-faculty under which the function is performed; thus the seeing faculty acts through the eyes, the hearing faculty through the ears, the tasting faculty through the tongue, the faculty of smelling through the nostrils, and the faculty of sentient touch is present throughout, since in this particular form of perception the entire body is an instrument in the soul's service.

The vehicles of touch are mainly centred in the nerves- which moreover are vehicles of the faculty by which the movements of the living being are affected- in them the soul-faculty concerned makes itself present; the nerves start from the brain. The brain therefore has been considered as the centre and seat of the principle which determines feeling and impulse and the entire act of the organism as a living thing; where the instruments are found to be linked, there the operating faculty is assumed to be situated. But it would be wiser to say only that there is situated the first activity of the operating faculty: the power to be exercised by the operator- in keeping with the particular instrument- must be considered as concentrated at the point at which the instrument is to be first applied; or, since the soul's faculty is of universal scope the sounder statement is that the point of origin of the instrument is the point of origin of the act.

Now, the faculty presiding over sensation and impulse is vested in the sensitive and representative soul; it draws upon the Reason-Principle immediately above itself; downward, it is in contact with an inferior of its own: on this analogy the uppermost member of the living being was taken by the ancients to be obviously its seat; they lodged it in the brain, or not exactly in the brain but in that sensitive part which is the medium through which the Reason-Principle impinges upon the brain. They saw that something must be definitely allocated to body- at the point most receptive of the act of reason- while something, utterly isolated from body must be in contact with that superior thing which is a form of soul of that soul apt to the appropriation of the perceptions originating in the Reason-Principle.

Such a linking there must be, since in perception there is some element of judging, in representation something intuitional, and since impulse and appetite derive from representation and reason. The reasoning faculty, therefore, is present where these experiences occur, present not as in a place but in the fact that what is there draws upon it. As regards perception we have already explained in what sense it is local.

But every living being includes the vegetal principle, that principle of growth and nourishment which maintains the organism by means of the blood; this nourishing medium is contained in the veins; the veins and blood have their origin in the liver: from observation of these facts the power concerned was assigned a place; the phase of the soul which has to do with desire was allocated to the liver. Certainly what brings to birth and nourishes and gives growth must have the desire of these functions. Blood- subtle, light, swift, pure- is the vehicle most apt to animal spirit: the heart, then, its well-spring, the place where such blood is sifted into being, is taken as the fixed centre of the ebullition of the passionate nature.