CHAPTER 4

Origin of the idea of our body
by means of modifications of the fundamental feeling

722. To form an exact idea of sensation,(130) we must set aside completely the idea of external bodies, which we always imagine as something striking our organs and producing sensations there. This cause must be considered as if it did not exist. Sensation is the only fact provided by consciousness and we must confine ourselves strictly to it.

723. The analysis of a particular sensation results in two elements: 1. a feeling which, as we have seen, is a modification of the fundamental feeling (cf. 705-706) (its matter is the modified organ); and 2. a believed representation or, as we call it, a perception of something different from us and our body (cf. 708-709). The first of these elements is subjective, a modification of the subject; the second, which I have called extrasubjective, is a perception of something different from the subject.
A correct understanding about the nature of bodies and the way we perceive them depends on an accurate distinction between these two elements, which are never found separated. Time spent on the distinction will not be time lost. We should also note that the first of these elements, the partial modification of our feeling, is the weaker of the two and therefore usually escapes our observation, which generally notes only the second to the exclusion of everything else.

724. In every corporeal sensation, we perceive our sensitive organ in a new way. Moreover, in every modification experienced by our sensitive organ there arises a perception of an agent different from us. The particular perception we have of our organ as perceiving is the modification of the fundamental feeling. As I have said, the fundamental feeling is a constant perception of the sensitive parts of our body in their first, natural state. The modified fundamental feeling is the perception of some part of our body modified and violently changed from its first, uniform, natural state.(131)
In order, therefore, to know a particular perception of our modified organ and distinguish it from the perception of an agent that accompanies the perception but is different from it, we must consider the nature of the fundamental feeling, of which the particular perception is only a new mode.

725. The fundamental feeling that comes from life is a feeling of pleasure, granted life in its natural, unspoilt state. It is uniformly and pleasantly diffused in all the sensitive parts of the body, without distinctive features. Thus, it would be impossible for anyone who has experienced only the fundamental feeling without ever experiencing particular sensations, to form the image or representation of our body (shape, size, etc.) which our sight and external senses offer. The fundamental feeling, then, is only pleasure diffused in a determinate way,(132) and its modifications are only a particular kind of sensible pleasure and pain.

726. These considerations give us a more complete definition of the fundamental feeling as 'a fundamental action that we feel done directly and necessarily in us by an energy that is not ours; the action is naturally pleasant but can vary according to certain laws, being in turn more or less pleasant, or even unpleasant.'

727. The action we experience of the fundamental feeling is the very essence of corporeal pleasure and pain. The particular modifications the action undergoes (according to a law we need not investigate at the moment) are particular perceptions of our organs felt more pleasantly or painfully. Pleasure and pain are thus feelings which must be distinguished from what, in a sensation, is external and has shape. We shall go on to describe this second element of sensations when our idea of the first is so accurate (if that is possible) that we can no longer confuse it with any other.
Corporeal pleasure and pain are simply a change experienced in our spirit; they represent nothing and have no shape. They are a fact; they are what they are, and cannot be understood by anyone without experience of them. Because such a change has nothing in common with anything outside it, it is undefinable and unintelligible to anyone who has not experienced it.

728. However, corporeal(133) pleasure and pain: 1. terminates in the subjective extension of the body (I call this extension therefore matter of the corporeal feeling); and 2. has different levels of intensity.

729. There is no difficulty in proving that corporeal pleasure and pain terminate in corporeal subjective extension.(134) For example, a square piece of metal placed on the hand is felt at every point it touches the skin; if the metal were a disc or some other shape, the points of contact with the skin would correspond to each shape.

730. In the same way, the fundamental feeling is present in all the sensitive parts of the body and therefore must extend and be referred to them; this is its mode of being. However this does not mean that just by looking we know the shape and size of the parts occupied by our pleasure or pain. The imagination is no suitable guide in these matters. Pure feeling, not the images seen by our eyes, makes us perceive the extension. Thus I call this extension subjective(135) to distinguish it from the extension presented by our sight or other senses relative to external bodies.

731. This should cause no difficulty if we reflect that this extension can be understood only as a mode of the feeling, as I have already said; the extension can change but never be separated from the mode of feeling.
We must not think that feeling and subjective extension are two entirely separate things, nor that feeling is first centralised and then spreads through the extension already felt as through something different from itself. This imaginary explanation, which is not given by careful observation, contains images taken from the sense of sight. All such images, however, must be excluded; we must restrict ourselves to the pure subjective feeling we are discussing. If we concentrate carefully on ourselves and observe our own feeling, refusing to be distracted by these images, we will easily recognise in our own subjective feeling that it is impossible for the soul to perceive an extension different from the same feeling with which it perceives that extension.(136)

Anyone wishing to observe the nature and modifications of the fundamental feeling we are discussing, must set aside every shape presented by sense; he must get rid of the idea of external extension given by the sense of sight or any other sense. He must turn in on himself attentively and reflect on the pains and pleasures he may be experiencing uniformly or variably in the different parts of his body. He will then find that these feelings have no shaped extension comparable to the extension we perceive with our eyes and other external senses in external bodies. However, he will find that they have a certain limitation, a mode. Now if we abstract this mode from the sensations and compare it with the extension perceived through our eyes or other external senses, we find that it harmonises with extension, and is called extension.

732. The following argument will be enough to show that the feeling of our own body must extend to all its sensitive parts. I agree with those who say: 'It is by touch that you project outside yourself the objects you see; otherwise they would be attached to your eye like a veil' [App., no. 27].

733. But they go on to say: 'In the same way sensation takes place in the brain. If communication between an organ and the brain is interrupted, you feel nothing; you locate the sensations at the affected organ by means of habitual judgments.' Here I part company with them altogether. In my opinion it would be impossible for bodies that I see to be projected outside myself by touching them if I referred the sensation only to some centre in my brain rather than to the extremity of my hand.

734. If by touching an object I see that I locate it outside myself, how do I locate my hand outside myself? For example, if I believe that the response of the sensitive nerve is in my head, why do I do not feel in my head the sensation I feel in the touch of my finger-tips? Why do I not feel the response in my spirit or along my arm or in some other part of my hand instead of only at my fingers-tips? In my opinion, this cannot be explained by acquired habit. If it could, we would have to demonstrate that there was first a time in our life when all sensations were not located at different points of our body, and later there were some means by which we learnt to locate them at the outside points; but no one has ever indicated this means nor can they.

If our eyes need touch to project things seen externally to the correct distance, and we conclude that the same must be true for the parts of our body felt by touch, then we must invent another sense of touch in the soul that would move the parts of the body outside the brain. This is absurd and denied by experience.
There is therefore in the soul a power that immediately, and not by acquired habit, refers sensations at various parts of the body and feels them there.

735. The extension of our own body is a mode of the fundamental feeling. But this fundamental feeling is either in its first, natural state or in its state of accidental, adventitious modification. Whatever its state however it always has the mode of extension. Hence we feel our body's extension subjectively in two modes: 1. by means of the fundamental feeling; and 2. by means of the modifications of this feeling, or the partial sensations we receive through our organs.

736. The difference between these two ways of feeling our body subjectively must be noted:

1. The whole extension of our sensitive body is perceived by the fundamental feeling. But when the fundamental feeling is modified by some external sensation, only the part of the extension affected by the sensation is felt.

2. The extension of the body is felt in a constant mode by the fundamental feeling. The part affected by a sensation is felt in a new mode, more vividly than the other parts, or at least in a different mode; it stands out from the other parts, and presents itself alone and isolated from them all in the feeling experienced by our spirit.

3. If life is present, the fundamental feeling produces a necessary mode of feeling; in a sensation the affected organ is felt in an accidental, adventitious mode.

4. The extension is felt equally with almost no variation by the fundamental feeling; at least we are certainly not conscious of any inequalities. In a sensation the organ is felt in very different modes, according to the different levels of pleasure or pain and the phenomena of colours, sounds, tastes, smells.

737. These four differences are sufficient to show clearly how unsuitable the fundamental feeling is for attracting our attention and coming to notice. It is connatural to us, one with and part of our nature. Hence there is nothing extraordinary or curious about it to engage our attention; it is in us as ourselves. On the other hand, no sensation of our own organ is essential. It is partial, new and vivid, accidental and changeable; it is equipped in every way for exciting our curiosity and attention; it attracts us to itself and makes us aware that we perceive the individual parts of our body with a subjective perception.
We can therefore conclude that, relative to the two subjective ways of feeling our body and its extension, the first (the fundamental feeling) easily escapes our observation, whilst the second makes itself known without any difficulty. It is not surprising that few people know they have this fundamental feeling, when the sensation of our own organs is so blatantly evident to all.

738. When one of our own sense organs is stimulated, the sensation we experience is a fresh confirmation of the existence of the fundamental feeling, which precedes the sensation. For how could we locate the sensation at a certain part of our body if we had no feeling in it? Note carefully: to say we feel the part at precisely the same time as we have the sensation is not sufficient. To feel the part means to locate the sensation at the part; this would mean we locate the sensation at the part without having any feeling there. Such a fact would be inexplicable.

739. The same can be said about the capacity for moving our limbs. If these were not naturally felt by us, they would be extraneous to us, and our will would not be able to move the limbs it wished with its internal act.
Without the fundamental feeling, therefore, two kinds of acts of our spirit would remain inexplicable and even absurd: the act by which our spirit locates a sensation it experiences at different parts of the body; and the act that imparts movement to them as it pleases. We must understand that it is myself who locates sensation and produces movement as an effect of its own very activity.

740. I call sensation subjective in so far as I feel my co-sentient organ in it; I call it extrasubjective in so far as I simultaneously feel an agent outside my organ. If we observe the fact of sensation attentively, we find there is no sensation in which we do not feel our sentient organ. Likewise, when we feel a modification of our organ, a perception of something outside the organ takes place in our spirit. We call this corporeal sense perception; it is very often so strong and vivid that it engages all our attention, so that we forget the organ completely and are unaware that we sense it.

741. The difference between corporeal sense perception and the sensation we have of the sentient organ is so important that we cannot be too careful in identifying it. The solution of a great number of psychological problems depends on the clear recognition and demonstration of this difference.

To indicate the co-existence of these two perceptions, I will begin with the sense of sight. We all accept that feeling our own eye, the organ of vision, is different from seeing bodies with our eyes. Anything perceived by our eyes has such a vivid, attractive presence that it draws all our interest, especially when our eyes have been conditioned and taught, so to speak, by touch. When our gaze is captured by a panorama or a beautiful work of art, we pay no attention to our eyes themselves where we are experiencing a weak sensation caused by the light striking them and passing through unnoticed. But this sensation, although unnoticed, is very real. Imagine a beam of strong light suddenly striking our eyes so that it is too intense for the pupils. At once we will feel and be conscious of an unpleasant sensation in our eyes which smart from a light too strong for them. In situations like this, we fix our attention on the organ affected by pain. We may conclude that, to be aware of feeling our perceiving organ, there must be a level of unusual, vivid pleasure or pain drawing our attention away from the exterior agent perceived by the organ.

What I have said about the eyes clearly demonstrates the elusive but true fact that granted a suitable modification of a sense-organ, we experience the two things I have mentioned, that is: 1. we feel the modified sense-organ; and 2. we perceive the exterior agent in a way compatible with our feeling. This perception has nothing to do with the sensation we have of the organ; but the perception is so indivisibly joined to the sensation that it forms one thing with it; one cannot exist without the other.

742. The same can be said of hearing, smell and taste. Hearing gives us sound, but sound is not the sensation we have of the acoustic organ with which we perceive sound, nor is it the exterior body. Sound, which arises when our organ is modified, has no similarity with the feeling we have of our organ; the stimulating action we feel is different from the action produced in us by our modified organ. The stimulating action accompanied by the phenomenon of sound is more assertive than the feeling we have of our organ and is able to attract our attention, especially when the action has special qualities. Thus, if I hear a flute or harp, I am attracted by the pleasant sounds and pay no attention to my ear, which would need to be modified in a painful way, for example, by a deafening explosion, to turn my attention from the sounds to the feeling of my ear. When such a thing happens, we usually cover our ears to protect them, which is a clear sign that we perceive the organ.

743. The same is also true for the senses of smell and taste: these are the phenomenal part of the sensation experienced when the organs are modified by their corresponding agents. For example, when we smell a carnation or taste honey, we can note the same two things. In the first place, my olfactory nerves are stimulated by particles from the carnation; it does not matter whether the stimulation is a slight vibration of the nerves, or s small mark or impression made on them. The question is: what do we perceive by smell? We certainly do not perceive the vibration or impression to which smell bears no resemblance. Nor does smell suggest any movement of, or form received by the olfactory nerves. Smell is a particular feeling arising in our spirit on the occasion of those minute and perhaps imperceptible movements of our nostrils. It is this feeling I call the phenomenon of smell. On the other hand the odorous particles striking our nostrils could be of sufficient force and intensity to cause us pain, and make us aware of the feeling of our nose, as happens when an offensive smell makes us wrinkle it with displeasure. Although the weakness of the impression may prevent this, we cannot say that the phenomenon of smell (in which we have the term of an external action) is not completely different from the feeling we have of the organ itself.
The same can be said about taste. The different form that our taste buds assume on contact with honey is not what we feel in the taste. The taste is the phenomenal part of the sensation and is completely independent of the perception of our palate.

744. Touch is a universal sense; it is equally present in all the sensitive parts of our body.(138)

745. The other four senses are themselves touch, from which they are distinguished only by the phenomenal part of sensation. When they are stimulated, these senses are subject to touch-perception and to this extent are the same as touch.(139) But certain kinds of touch affect our spirit with four kinds of phenomena: colour, sound, smell and taste. These phenomena distinguish the organs and, as a group, are different from touch which is common to them all and diffused through the rest of the body.

746. The sense of touch in its subjective element is only the receptivity of the fundamental feeling for experiencing a modification. But because the fundamental feeling is extended to all the sensitive parts of the body (in other words, this extension is only the mode of being of that feeling), the feeling changes when this mode of being changes. This is why we experience sensations of touch when some suitable motion takes place in our body.
The four specifically different phenomena of which we have spoken, and others which need not be listed here, are united to some of these sensations.

747. Because the sense of touch is the foundation of all the different kinds of sensations, we also feel a modification of the sentient organ although we do not always advert to it. In fact we rarely advert to a modification of those senses in which the four sensible phenomena are found. The intensity and singularity of these phenomena, like their usefulness and necessity, attract all our attention away from the unassertive sensation of the organ itself. But this does not happen so noticeably in the sense of touch which, phenomenally weaker, concentrates our attention more on the organ itself.
The second way of perceiving our body (by means of particular sensations) is not, therefore, essentially different from the first. It is subjective in so far as, together with it, we sense our organs as co-sentient, not just as felt; in short, we feel them as forming one thing with the sentient subject, myself.

748. But in these two ways of feeling and perceiving our body, the matter of feeling and of sensation (the body itself) is always the same. Hence there can be no contradiction between them. What makes these two ways of feeling coherent and equal is the fact that we locate feeling and sensation at the same points in space.

(130) The word 'sensation' is generally taken to mean an acquired, particular sensation.

(131) When I describe a particular perception of our sensitive organs in this way, I am not taking anything for granted. Certainly modification of the organ is part of the definition; but the modification is not gratuitous from the moment the organ itself is a body and therefore part of the energy acting in us and simultaneously producing the fundamental feeling.

(132) Although the pleasure of life is truly diffused throughout all the parts of our body that have feeling, we cannot use the expression 'We refer the primal feeling to different points of our body's extension' with the same meaning without putting the reader on his guard. This way of speaking could be confusing because it is not the way we know the body in the primal feeling, nor therefore see or touch its extrasubjective extension or, a fortiori, its parts. When we speak about the feeling of the whole of our sensitive body, we should always remember it means nothing more than a mode of that pleasure. This mode becomes clothed, so to speak, with external, figured extension at the time we obtain the perception of our body with our external senses. But more of this in a later chapter.

(133) I use the word 'corporeal' as a simple sign to indicate the difference from any other feeling, without going more deeply into the difference and discovering a third element of sensation.

(134) Corporeal pleasure and pain are experienced passively in the spirit but at the same time are accompanied by some activity of the spirit. I cannot stop at this point to describe how these two conditions are united - I have touched on this elsewhere. It is enough to note that in so far as pleasure and pain are acts of the spirit, it can be said they terminate in extension; but in so far as they are experienced, it is more accurate to say that corporeal extension terminates in them with its action. The reason for the truth of these two seemingly contradictory ways of speaking must be found in that strange but true and perfect unity between what is subjective and what is extrasubjective, between what is active and what is passive at the time of the action.

(135) This name does not indicate its nature because all extension is extrasubjective; it indicates its intimate union with sensation which is itself subjective and takes its mode from this extension.

(136) Extension is therefore the matter of the feeling, since matter and form are one thing.

(137) We should not forget that this subjective extension is known to us only as a mode of the fundamental feeling without any shape, unlike the extension of external bodies.

(138) The ancients also noted that all the senses are ultimately touch. St. Thomas says: omnes autem alii sensus fundantur supra tactum (S.T., 1, q. 76, art. 5).

(139) We have seen that touch has a double nature: it is simultaneously subjective and extrasubjective in so far as we perceive 1. the sentient organ (the subjective part) and 2. the touching, external agent (extrasubjective part). From what I will say later, it will be more evident how the twofold sensation and the four phenomena are present in the particular senses we are discussing.