Chapter 3

Origin Of The Idea Of Our Own Body, As Distinct From Exterior Bodies,
Through The Fundamental Feeling

692. Bodies exist as substances different from God and ourselves. As the proximate cause of our sensations their essence consists in a certain energy acting upon us, relative to which we are passive. And any activity, different from our own, constitutes a different existence [...].

But we do not think of body only as a substance causing corporeal sensations. We bestow upon this substance other qualities such as extension, shape, solidity, mobility and divisibility, and generally speaking all the physical and chemical properties that bodies manifest in their relationship to one another and to us. Above all, body, with its capacity for life when duly united with the spirit (cf. 668-669), also possesses a capacity for change, causing pleasure and pain, sensations of colours, sounds, tastes, and so on, in us. This capacity can even deprive the body of life by separating it from the spirit. We have yet to show how the body is known by us as the subject of these properties and capacities. If we succeed in doing this, we shall also be able to explain the ideas of the various qualities attributed to the body.

It is clear that we are about to enter the wide field of physical nature where we have to deal with life, feeling, and different kinds of sensations in order to complete our study of the ideas of matter and of body.

693. Bodies possess a physical relationship amongst themselves, and a relationship with our spirit. Observation enables us to know the facts constituting and determining these two relationships. In the physical relationship among bodies observation shows that, when bodies are related to one another locally, various changes take place, according to stable laws. This capacity for receiving modifications or alterations corresponding to their respective positions results in the mechanical, physical and chemical properties of bodies.

But are these properties, such as propulsion, attraction, affinity and so on, true powers of the body in such a way that bodies are the true causes of all the modifications to which they are subject?
This question has nothing to do with my argument. I mention it in order that it may not distract the reader if it should occur to him. We are not asking if propulsion, attraction, cohesion, and affinity are true forces; we merely want to know exactly the simple facts presented by observation(1) .

694. All these facts can be reduced to the following formula: 'When bodies are placed in certain positions relative to one another, alterations occur which are constantly the same, given the same bodies and the same positions'(2). We now ask how we form the ideas of these alterations, ideas presented to our spirit by the alterations.

We mentally conceive mechanical, physical or chemical alteration or change in bodies through their presence in certain positions only in so far as: 1. the modified body acquires a different capacity for acting upon us by causing internal or external sensations different from those caused previously; 2. the modified body acquires a different capacity for modifying another body --- in the last analysis, this modification is reduced to the different capacity that the modified body possesses for acting upon us. When a body changes colour, taste, hardness, extension, force, or any of the feelable qualities resulting from a new state, it has changed only its capacity for producing sensations in us.

Only through our senses can we come to know when a body receives or loses some property or power without changing its feelable qualities. If the change were of such a nature that it presented no direct or indirect sign to our senses, we would not perceive it in our feeling, nor could we think, imagine or assert it(3). If we adhere to pure observation, we have to say that any change in a body must be feelable by our senses in order to be something for us. It must finally produce some effect or action on our senses. Any difference found through such changes on the part of bodies can be reduced to a change only shown directly or indirectly to our senses. If one body changes colour in the presence of another, as grass and leaves become green on contact with the light, that body has suffered a change shown immediately to our senses.

If I magnetise a needle, the change in the needle is not immediately obvious to my senses. Its new properties are shown only by its power to attract other ferrous metal, or to point towards the pole when set on a balance. But seeing the needle act in this way means that I now receive a certain series of sensations I did not possess while the needle remained unmagnetised. As far as I am concerned, the new power acquired by the needle is reduced to certain new capacities for producing different sensations in me. And this is true whenever we examine the effect of one body's action upon another; any changes mentally conceived in a series of bodies acting upon one another are only capacities for acting upon us.

Let us imagine that the last of these bodies acts upon us. Through it, and only through it, we know the changes which have taken place in the others. If the series of bodies is called A, B, C, D, E, F, Z, we find that the change suffered by Z, which has affected us, can be defined as follows: 'The change in Z consists in its losing the capacity for producing one series of sensations in us, and acquiring the capacity to produce another series'. I go on to define the change experienced by F as follows: 'The change in F consists in acquiring the capacity for bringing about the change described in Z'. I have experienced the alteration in Z through my senses, but the change in F is known only through that in Z. If I now wish to substitute the known value of Z in the definition of the change in F, I produce an awkward definition, but nevertheless the only one possible: 'The change in F consists in its capacity for producing a change in Z through which Z loses its capacity for producing one series of sensations in me and acquires the capacity for producing another'. In the same way, the change in E can be defined only in relationship to the change in F, and so on, back to A.

Amongst the alterations in all these bodies, only that of Z is known to me of itself. The rest are known as first, second, or third causes of Z, and so on. Everything I know about the possibility of bodies modifying one another is reduced to Z's new power to modify me. Knowing the modification I experience, I know the capacity producing it in me. Knowing this, I know relatively the causes more or less proximate to it(4).

Our observations show clearly that all mechanical, physical and chemical qualities or properties constituting the relationship of bodies to one another are (when we limit ourselves to observation alone) simply powers capable of modifying us and producing sensations within us(5). Hence, all the ideas that we have or can have of these properties are reduced to the different impressions the bodies make upon us, and to the different feelings they cause in us. We can mentally conceive only those mechanical, physical and chemical powers of bodies that either modify us, or modify and change the powers modifying us.

Our question, therefore, has been reduced to a careful examination of the relationship of bodies to us as we explain the origin of their feelable qualities, to which all other qualities are finally referred.

695. In speaking of the mutual connection of bodies, I have kept to pure fact and avoided difficult questions. I intend to follow the same method in indicating the connection of bodies with ourselves, and I ask readers to remember that I am confining myself to the limits placed by observation. I mention this to prevent a fruitless search for something not contained in the work.

Observation does, however, take us further in this field than it did when we examined the connection of bodies amongst themselves. We ourselves are one of the terms of the present relationship, and it is obvious that we can observe ourselves more intimately because our consciousness shows us the facts taking place in our spirit. While observation cannot tell us if bodies are the true causes of the modifications discerned in them, we can, given certain relative positions of the bodies in question, distinguish our own from other actions by simple observation on ourselves.

696. Observation of the connection of bodies with ourselves offers three distinct relationships which can usefully be indicated here.

The first relationship: an intimate bond between our sense-principle and a body that becomes its term (matter). This I call life(6).

The second relationship: a fundamental feeling(7) proceeding from life, that is, from the first bond. Through this feeling, we habitually feel all he material, sensitive parts of our body.

The third relationship: the capacity possessed by the sensitive parts of our body for being modified in certain ways. Various species of external sensations correspond in us to these modifications, and in them the perception of bodies external to our body.

697. The connecting bond between external bodies and ourselves consists, according to the idea we have formed of it, in considering these external bodies as capable of modifying the sensitive parts of our body and providing our spirit with varied sensations.

698. First, we have to clarify the opinions proposed, then prove them. To clarify them, we begin by establishing clearly the distinction between life and the habitual, fundamental feeling caused by life. We said that life was a certain intimate, unique bond of spirit with matter. In this bond, matter becomes the constant term of the sense-principle in such a way that the two things form a single underlying factor(8).

Life is not feeling, or at least not feeling as observable by us; feeling is an effect of life. We can see this if we realise that all the parts of our body, provided we are alive and healthy, enjoy a life of their own and are joined to us according to their condition in such a way that this bond is called life. Thus animated parts in us carry out the vital acts proper to them, the principal of which are nutrition, heat, and vital movement, which result in incorruption and the capacity of each of the various parts of the body for different functions. But the seat of feeling, as we have seen, is not every part of the body, but only those parts we call nerves. We say this without wishing to enter the physiological field, foreign to our argument(9).

699. We can usefully employ our imagination to form a clear concept of the sensitive body. Let us picture the human body present to us simply as a network of nerves and bereft of all parts that have no feeling. This is the sensitive body which, when joined to us vitally, enables us to feel. In my opinion, we perceive this body habitually and uniformly with an innate, fundamental feeling which, however, we do not advert to easily because of its continual sameness, although we are aware of the changes that take place as one or other of our nerves is touched. Stimulation of the nerves produces a more marked sensation, easily adverted to because it is unusual, temporary and incomplete, not universal and constant like the first, stable feeling which, diffused throughout the nervous system, often goes unobserved, even by philosophers, because it is connatural and permanent.

700. We now have to examine in detail: 1. how we feel our sensitive body in which the fundamental feeling is present; and 2. how we perceive external bodies which only touch and stimulate our sensitive body.
Because bodies, as we have said, are perceived by us as substances causing sensations, and as subjects of corporeal qualities, it will help us if we apply what we have noted about the perception of bodies in general, first in a special way to bodies that feel, and then to feelable, non-sensitive bodies. We can then discuss both kinds considered as subjects of the qualities indicated in them, qualities which are either feelable or reduced to feelable qualities (cf. 693-694).

701. First, I note that our body (and when I speak of our body I always mean the part where we are sensitive) is perceived in two ways.

1. Like every other external body it is perceived by touch and sight or, in a word, by all five sense-organs. When I perceive my sensitive body as acting on my five organs, I do not perceive it as sharing in sensitivity (this must be clearly understood because of its supreme importance), but as any other external body which, falling under my senses, produces sensations. In this case, one organ of my body perceives another. It is as if someone were to anatomise and perceive the nerves of another living, sensitive being whose nerves are not sentient to the person anatomising them, but only to the person to whom they belong.

2. We also perceive our body through the universal, fundamental feeling by which we feel life in us (a feeling witnessed by our consciousness, as we shall see later), and through the modifications experienced by the fundamental feeling itself in its adventitious, particular sensations.

These two ways of perceiving our sensitive body can be distinguished appropriately enough by the words 'extrasubjective' and 'subjective'. When we perceive our body subjectively, through the fundamental feeling given to us with life itself, we perceive our body as one thing with us. Hence, through its individual union with our spirit, it too becomes part of the sentient subject, and we can truly say that it is felt as co-sentient by us. On the contrary, when we feel our body extrasubjectively, in the way we feel external bodies through our five senses, it is outside the subject, like other bodies, and different from our sensitive powers. We do not feel it as co-sentient, but merely in its external data, in so far as it is capable of being felt. We must take great care to distinguish the subjective from the extrasubjective way of perceiving our body. A great part of what we have to say depends upon this distinction.

702. The subjective way of perceiving our body is twofold. We perceive the sensitive parts of our body subjectively with both the fundamental feeling, of which we have spoken, and the modifications experienced by this feeling when impressions are made on the nerves.

703. The second, subjective mode of perceiving our body is shown by an accurate analysis of external sensations which reveals two things in every sensation:

1. the change arising in the sensitive, bodily organ which, as a result of the change, is felt differently, that is, the fundamental feeling suffers modification;

2. the sense-perception of the external body that has acted upon us.

Let us take the sense of touch as our example. When we rub some rough surface against the back of our hand, we feel two things: the hand and the surface rubbing against the hand. The first is what I have called a modification of the feeling of our body; the second is the sense-perception of the rough surface.

704. This twofold quality of sensation must be noted with extreme care. But here it is sufficient to indicate the connection between these inseparable, simultaneous feelings included in the single fact of sensation. What I am saying is this: on the one hand, the feeling that we experience through the simple change(10) occurring in our bodily organ is a modification of our fundamental feeling; on the other, we have a sense-perception of an external body accompanying this modification, but altogether different from it. This fact occurs in us on the occasion of the first change and feeling, although we are unable to find a necessary connection of cause and effect between these two things. Nevertheless, as we shall see, we can note the presence of a single cause of both the subjective feeling and the extra-subjective perception experienced in the senses.

Notes

(1) Nevertheless what we shall say will throw light on the question.

(2) Any new condition changing the results would be reduced to a body's approaching or distancing itself, which is excluded by the formula. It is understood that no account is taken of the action of spirits; bodies alone are considered in their mutual relationships.

(3) If we were told about it, we would either have already experienced it with our senses, or not. In the first case, we would have some positive cognition of the fact, together with belief in what we have been told; in the second case, we would only believe in such a change, our cognition of which would be merely negative.

(4) My knowledge of corporal capacities or forces, derived from their activity upon me, is the first cognition I can possess about them. This must not be taken to imply that I cannot deduce other truths about bodies from my first cognition. I simply affirm that my first experimental cognition is the basis of all my other reasoning about corporeal qualities.

(5) This does not remove from sensation the extrasubjectivity we have spoken about, and which we intend to explain more fully later in this work.

(6) That is, animal life.

(7) Proofs of these assertions will be given later.

(8) We do not want to describe the union here, but simply indicate it under its own name to avoid confusion with any other kind of union.

(9) Some physiologists have pointed to apparent anomalies in this law. For our purposes, it is sufficient that sensitive and non-sensitive parts are present in the human body, given certain circumstances and moments.

(10) The change in our sensitive organ is still not feeling. Nevertheless, given that change, we feel because of our habitual feeling of the organ, whatever its state. Hence its changes are also felt. But we must not confuse: 1. The physical impression on the organ, with: 2. Our first feeling of the same impression.