Laws of Animality

Chapter 2

The law of sensuous instinct

1799. The sensuous instinct is simply an action following from the life instinct and properly speaking from its third function which I called the excitatory function. The first motor principle is the same; it is the act positing the animal form. But the proximate motor principle in the sensuous instinct is the feeling, already posited in being, from which a new activity arises. The sensuous instinct, therefore, can be defined as: 'That movement of the life instinct which, once a feeling has been produced, makes the instinct become as intense and complete as possible by means of suitable excitations.'

1800. These excitations can, however, be either stable, that is, continually repeated by means of a fixed law (as happens in the fundamental feeling of excitation), or temporary and accidental. In this latter case, they briefly modify the fundamental feeling. I use life instinct to indicate the function which tends to preserve or reproduce stable excitation; I use sensuous instinct as a name for the function which tends to obtain temporary, partial excitations for the stable feeling. These excitations give rise to sense-experiences and passions. This distinction is useful for science and of some importance. Indeed, stable excitation characterises, as I said, the fundamental feeling, and enters consequently as an element of the basis for the philosophical classification of animals. A determined animal form ceases when its stable, characteristic stimulation ceases.

1801. Granted these observations, I define the law of sensuous instinct as follows: 'Sensuous instinct, through temporary stimuli and excitation, tends to enhance to the greatest possible degree, the partial, temporary sensations which, as pleasing, are aroused in the fundamental feeling.'

1802. Consequently, the following functions are distinguished in the sensuous instinct:

Function I. Sensuous spontaneity. The sensitive principle employs this function to further, with its spontaneous activity, every exterior stimulus applied to an animal for the sake of exciting feeling towards a second, more perfect act that is, to a pleasing sensation. In other words, the aim is to increase and prolong the effect of a pleasing sensation (an activity of the soul co-operating in all sensations).

1803. Function II. Sensuous propensity. The sensitive principle employs this function to actuate and dispose itself to its second, pleasing acts by means of the synthetical, animal force(7) which, granted some stimulus (pleasing sensation), inclines the animal towards a further sensation presented to it as the completion of the first.

1804. Function III. Sensuous aversion. This is the opposite of sensuous propensity and arises when the synthetical-animal force is employed to impede the completion of some adverse propulsion (displeasing sensation) disturbing the sensitive principle.

1805. Function IV. Sensuous contra-spontaneity. The sensuous principle employs this function to combat the force of every exterior stimulus applied to the animal for the sake of impeding the feeling, that is, of causing a painful sensation. The aim is to retain the fundamental feeling in all its fullness and with it the particles to which it adheres, but which in this case are under pressure to separate from it or upset it.

1806. Function V. Motor-sensuous spontaneity. This is a consequence of the first four functions. In fact, an action in the animated body and its matter corresponds to the four tendencies and movements of feeling, according to the principle already stated: 'Extrasubjective phenomena correspond to all modifications of feeling.'

1807. However, this last function, considered in its effects, is found at six moments:

First moment of motor-sensuous spontaneity. It manifests itself in the tendencies and movements (great and small) produced in the extrasubjective animal body by the whole complex passion summed up under the name concupiscent mobility.

1808. Second moment. It manifests itself in the tendencies and movements (great and small) received in the extrasubjective animal body from the activity posited by the motor-sensuous spontaneity in its actual pleasing sensations and passions. This activity I call voluptuous mobility.

1809. Third moment. It manifests itself in the tendencies and impediments to movement received in the extrasubjective animal body by any complex passion which resists displeasing excitation and does not allow itself to be moved easily. This passion I call withdrawal mobility.

1810. Fourth moment. It manifests itself in the tendencies and movements (small and great) produced in the extrasubjective animal body by any complex passion which, when the displeasing outcome of a species of movement becomes clear, endeavours to determine contrary movements. I call this adverse mobility.

1811. Fifth moment. It manifests itself in the tendencies and movements (small and great) received in the extrasubjective animal body from the effort made by the sensitive principle to maintain its intensity and movement when exterior, contrary and obstructive forces act upon it. I call this irate mobility.

1812. Sixth moment. It manifests itself in the tendencies and movements (small and great) received in the extrasubjective animal body from sympathetic mobility. This is the name given to mobility subject to imagination and thought. When the imagination presents sad images, this mobility gives rise in the body to movements which depress the subject's forces; the contrary occurs when the imagination presents happy images. This moment is one of the sources of disruptive forces in nature.(8)
All six moments are concerned with effects manifested to external, extrasubjective observation as a consequence of feeling which takes up different tendencies and is considered as the subjective cause of these effects. The six classes of effects are invariably reduced to movements because movements are the extrasubjective phenomena corresponding in an animal to equivalent feelings which, in turn, are subjective phenomena parallel to the extrasubjective.
All these functions and operations of the two instincts can usefully be seen in the following synoptic schema [p. 12].

1813. Because the effect sought by the sensuous instinct with its activity is that of enjoying the temporary excitation of feeling, the last function of this instinct, that is, motor-sensuous spontaneity, often produces movements in the body and in the matter of the body which oppose those resulting from the tendencies of the organising function of the life instinct. The motor-sensuous spontaneity often becomes a disorganising principle struggling against the organising principle. We have, therefore, another source of the disruptive forces of animal nature.(9)

1814. This disturbance would, however, be rendered impossible if the body were fully dominated by the life instinct. As I said, this fact does not involve contradiction. I should add that such dominion pertains to the ideal of animal life, that is, it would be the ultimate degree of such life. Indeed, if the life instinct were, in addition, to receive sufficient strength to retain the corporeal molecules without any possibility of losing them, or if it were at least sufficiently protected so that no foreign force could remove them, no struggle would arise between life and sensuous instincts. The result would be immortality.

1815. Here it will be helpful to examine briefly Brown's concepts. What relationship exists between Brown's excitability and the different activities I have attributed to life? - If we consider that Brown drew his concept of excitability from the effects produced by stimuli on the living body (effects which he saw as sense, muscular movement, thinking activity and affections of the spirit), it must be a source of great wonder to realise that, according to him, the property of excitability is one and indivisible in the whole animal machine and can consequently be diversified only quantitatively in the different parts of the animal machine. Surely it has been shown unequivocally (if we depend on consciousness, the only reliable witness to this fact) that stimuli do not bring the phenomenon of sensation into being in all the parts of our living body? Surely it is absurd to attribute thought to an organ or to any living machine whatsoever?

The Scottish doctor confuses three extremely distinct classes of effects: 1. movement, an extrasubjective phenomenon which is manifested not only in the muscles but in each of the four tissues, that is, in cellular, vascular, muscular and nervous tissues; 2. animal feeling, a subjective phenomenon which is not recognised through any extrasubjective observation, but only through the witness of consciousness; and 3. thought, a subjective-objective phenomenon which is totally outside extrasubjective observation and is per se revealed immediately as a result of consciousness. Again, affections are in part a consequence of animal feeling and in part of thought. They are divided and located in the last two classes. It is impossible to bring together in a single property effects of such disparate essences which, moreover, are strongly opposed to one another.

If, therefore, we want to understand excitability as a single property enjoyed, to different degrees, by every part of a living body, we need to restrict its meaning to the property, possessed by the animal body, of moving itself as a result of stimuli with a given movement proper to itself. This property could be called contra-distension and, relative to sense-experience, should be recognised as a merely concomitant effect of distensive- contractile movement. This effect does not always follow such movement unless it is produced in a certain way and in certain determined, sensitive parts of the animal body which therefore are called 'sensitive'. Finally thought, far from pertaining to any part of the body, is a fact which does not adhere to any corporal organ. The slightest consideration shows that it is altogether immune from corporeal concretisation, and is even less like movement than weight is like colour.

Thought may indeed arise when distensive-contractile movement, which is produced not in all but in certain determined parts of the body, and not in all but in certain determined ways, posits a sense-experience in being. Nevertheless, it is neither similar nor analogous to contra-distension. It is not even concomitant with this distension, although it is concomitant with sense-experience, which provides matter for thought and stimulates the sensitive, rational soul to undertake its own proper operations in the way we have explained.(10)
Brown's excitability, therefore, can only be the property of contra-distension. This is the only case in which it is a homogeneous property, and specifically the same for all parts of the animated body.(11)

1816. We have, therefore, determined a reasonable meaning for excitability. From here onwards, I shall call it 'extrasubjective excitability' to distinguish it from excitability of feeling. I can now reply to the question posited previously: 'What relationship is present between Brown's excitability, that is, extrasubjective excitability, and the various activities I have attributed to the vital principle?'

First, it is clear 1. that extrasubjective excitability does not include all the properties and activities of the living body; 2. that it must be found within the sphere of the two functions I have called the organising function and the function of motor- sensuous spontaneity; 3. that more is contained in these two functions than in extrasubjective excitability alone.

1817. Indeed, there are three moments of the organising function which I have called retention, reproducibility and vital motor spontaneity. The moment of retention is however totally different from excitability; it does not refer to external stimuli as excitability does. The moment of retention is simply the endeavour made by the vital principle to preserve in a living state molecules which are already alive. It retains them to prevent their leaving its sphere of action.

Reproducibility also requires stimulating matter which must be assimilated to the living body. The effect of the reproductive force is not only distensive-contractile movement, in which alone extrasubjective excitability consists, but also the assimilation of the stimulating matter which, on ceasing to be a stimulus, is changed into part of the living body(12) and itself becomes excitable.

We now have to examine animal motor-spontaneity. This certainly needs continual stimuli, but produces, in addition to contra-distension, the diminution of reciprocal coherence between the molecules or elements with which the living body is structured. This facilitates interior movements which heighten the level of feeling. Animal motor-spontaneity, therefore, has a double effect: 1. it makes molecules and the elements composing them lose the reciprocal adherence they would possess if physical attraction and chemical affinity could operate freely. Again, I believe it prevents their possessing too many points of contact. All this is necessary to facilitate the excitatory movements of the fundamental feeling. This effect is totally different from extrasubjective excitation; 2. it seconds, augments and increases excitatory movements of feeling. This second effect is the only one pertaining to extrasubjective excitation, but with one limitation which I shall explain later.

We come now to the moments of the other function, which I call motor-sensuous spontaneity. I distinguished six of these moments and called them concupiscent, voluptuous, retentive, adverse, irate and sympathetic. I believe that all these species of animal movements can probably be reduced to their form, to contra-distension. In this case, they may have some reference to Brown's excitability, but here again there is one limitation.

1818. This limitation is similar to that already indicated when I spoke of the second effect of vital motor spontaneity. I will explain the limitation here.
If we grant that extrasubjective excitability is the only property of the living body, it follows that its effect, excitation, is in proportion to the primitive stimuli. If these cease, excitation also ceases. In this case, there is no place for the motor spontaneity which I have divided into its two branches of vital and sensuous motor-spontaneity. In other words, there is no longer any place for an increase and continuation of movement which continues in the living body after the cessation of primitive stimuli. But if we admit, on the contrary, that sensitivity is a potency producing extrasubjective effects, and is essentially distinct from excitability which it precedes, we can understand how, despite the cessation of exterior stimuli, movements can still continue and follow one another in the human body according to determined laws. There is a principle to which we can fittingly attribute such spontaneous movements. These movements are undeniable, and Italian doctors, meditating on Brown's theory in the hope of perfecting it, have recognised them. They have called them diathesi in imitation of that diseased condition, out of proportion to external stimuli and independent of them, which passes through a certain stage with successive, diseased processes.

If we now consider both vital and sensuous motor spontaneity as potencies aroused by external stimuli and posited at a certain degree of orgasm, we can, under this aspect, suitably attribute to them Brown's property of extrasubjective excitability. But if we consider that this aroused activity is maintained for some time of itself after the removal of the primitive stimuli, and unfolds in reciprocal actions producing a series of states and affections in the human body (where a preceding state causes a subsequent state), motor spontaneity must be recognised as a greater, highly different activity from extrasubjective excitability.

Moreover, we need to consider that vital motor spontaneity differs in degree in the organs of the human body, and that sensuous motor spontaneity is itself variously distributed and probably does not conserve the unity of its principle, as we shall see. In this case, we have some explanation of the fact of diseased localities illustrated by Professor Fanzago and other famous doctors, a fact which cannot be explained solely by Brown's universal excitability. Some light is also thrown on what doctors call irritative illnesses.

1819. All this shows that feeling cannot be considered as a simple effect of excitability and stimuli, as Brown thought. Rather, feeling is to be considered as the true cause even of extrasubjective excitability. To my mind, this excitability can only be an effect produced in the body by activity connected with feeling.

1820. The following, therefore, is the series of causes and effects in all animal phenomena. These phenomena are divided into two great classes, subjective and extrasubjective.

1. The fundamental feeling (subjective), which possesses the tension or effort which we have described elsewhere.
2. Movement (extrasubjective) of the sensible parts of the human body. These parts are excited by external stimuli in a way suited to excitation of the fundamental feeling.
3. Sense-experiences (subjective), that is, modifications of the fundamental feeling aroused by excitation.
4. Efforts and movements following on sense-experiences (extrasubjective), which I have brought together under the two activities named organising function and motor-sensuous spontaneity.

1821. These series show that subjective and extrasubjective phenomena alternate, and that all activity moves from the subjective principle, which produces subjective phenomena succeeded by a class of extrasubjective phenomena. These in turn are succeeded by another class of subjective phenomena and these by extrasubjective phenomena, and so on.

Notes

(7) AMS, 416-494.

(8) AMS, 401-415.

(9) AMS, ibid.

(10) A New Essay concerning the Origin of Ideas.

(11) This definition of Brown's excitability harmonises with the laws attributed to it by Professor Medici:'1. Excitability reacts in different ways in different tissues of the body.'2. This force needs powers or stimuli of different qualities to produce its effects.'3. It reacts with various levels of energy in proportion to the various degrees of force exercised by the stimuli.'4. Its action is made more lively by the variety of the excitatory powers.'5. In the ordinary actions of life it continually decreases, that is, reacts with ever less energy.'6. After cessation, or even decrease of stimuli, excitability returns, lively and ready, as it was previously.'7. Excitability reacts in inverse proportion to the action of preceding stimuli.'But these laws would require further special determinations.

(12) This kind of stimuli can aptly be called reproductive stimuli to distinguish them from other stimuli which are stimuli, and nothing more. The name 'reproductive' was given by Dr. Luigi Emiliani, who in his Memoria already quoted writes: 'It is easy to understand that the presence of reproduction does not depend solely on some property suitable for producing it, but also requires the presence of means with which to form it. These means can be called 'reproductive' in accordance with the effect they produce.'