Part Five

CHAPTER 2

Origin of our idea of corporeal substance

672. Having shown that the sentient subject (the spirit, myself) cannot be what is understood in the word 'body' we must now see if what we mean by 'body' really exists, or indicates an imaginary concept without content. Our aim is to discover if there is such a thing as corporeal substance, as common sense affirms, and if so how we attain our idea of it.
When we have found the way in which we form our idea of body and persuade ourselves, as we form this idea, that bodies really exist, we shall also have demonstrated the existence of bodies. Such a demonstration, taking its origin from the persuasion of the existence of bodies, is valid provided that reasoning, dependent upon perception for its first link, is capable of finding or proving the truth. Most people do, in fact, take the existence of bodies as the most certain of all things, but modern sceptics have tried to throw doubt upon ordinary reasoning. In the next Section of the work, we shall refute the objections against the validity of reasoning, and thus reinforce what we intend to say here about the existence of bodies.

673. We have said that the concept underlying the word 'body' is that of 'a proximate cause of our sensations' and that 'this cause is the subject of qualities' (cf. 667). We have to show, therefore, how we obtain a reasonable persuasion of the existence of 'a cause of our sensations different from ourselves', and that this cause is 'the subject of qualities'.(107) This will not be difficult if we remember what we have said.

674. Sensations presuppose a cause different from ourselves.
External sensations are facts towards which we are passive (cf. 661-666).
Passive facts are actions done in us of which we are not the cause (ibid.).
Such actions suppose a cause different from ourselves because of the principle of cause (cf. 567-569).
Consequently, sensations suppose a cause different from us. And this was what we had to show.

675. We have seen that sensations suppose a cause different from ourselves (cf. 674).
It was shown that a cause is always a substance (cf. 620 ss.).
The cause of our sensations, therefore, is a substance.

676. Because our sensations are actions done in us of which we are not the cause (cf. 662-666), we experience energy capable of changing us. This energy is a substance working upon us and we call it 'body' (cf. 667). The action of a body upon us is, therefore, the effect not of any particular power of the body, but of the body itself. In our definition of body, we do in fact call it that which modifies us in this way. Moreover, we recognise no other co-ordinated powers in the agent indicated by the word 'body'.
But the action of an operating substance is always intimately joined to the substance itself, because the force or energy of an ens is inseparable and indivisible from the ens itself. The substance which causes our sensations is therefore joined to them immediately.(108)

677. The energy or force which we experience as producing our sensations is limited because its action within us, of which we are not the cause, is limited.
But this is the energy which gives us the idea of substance or, as we could say in equivalent terms, we perceive in that energy or force an ens, the cause of our sensations, which is distinct from ourselves. But the ens in which we mentally conceive this energy is as limited as the energy we experience because this ens is for us only the energy itself considered as existing.
Hence the ens we think of as the substance and proximate cause of our sensations is limited.

678. This proposition is evident.
We cannot name anything unless we know it and according to the way in which we know it.
Hence we cannot name it except in so far as we know it.

679. Words express entia in so far as we know them intellectually.
The meaning of words is limited, therefore, by our knowledge.
It is an abuse of language, leading to equivocation and sophisms in our reasoning, to use a word with a wider sense than the concept of the ens it names; we are using it for what it could mean, although we have no idea or perception of what this may be. Words used like this have neither the meaning nor the purpose given them by the human race.

680. Defining a body is equivalent to stating the use made of the word 'body'.
If we wish to define this word, therefore, we can do it either by analysing all the ideas which form its meaning, or by indicating some characteristic idea, wholly proper to the ens under review, which will lead us to the ens named by the word in question.
For the present, we need to clarify the word 'body' only in the second way. Later on, we shall define it more fully and closely.

We have seen that we form the idea of body from that which acts in us, that is, from the force or energy we experience in sensation (cf. 640-643).
Because this energy is limited, we can draw from it only the concept of a limited ens (cf. 677).
All our knowledge of bodies is therefore that of limited entia.
But words express entia in the way in which we perceive and know entia (cf. 678).
The word 'body' was therefore invented to signify a limited ens. Using it in some other sense would be to abuse it (cf. 679).

681. Bodies are the proximate cause of our sensations (cf. 667). Bodies are limited entia (cf. 680).
God is not a limited ens.
Therefore God is not the proximate cause of our sensations.

682. The proximate cause of our sensations is an existing substance.
This substance is called 'body'; it is not God (cf. 681).
Hence bodies exist, and cannot be confused with God.

683. This demonstration of the existence of bodies refutes Berkeley.
His sophism began by falsifying the idea indicated by the word 'body'.
If this idea is correctly understood, it is impossible to confuse it with God. It is the idea of something completely limited, that is, of the energy we feel acting on us and underlying sensations, something thought in itself.
Our understanding, thinking about this force we experience, supplies only existence, and has no right or reason to add anything else. Hence the force remains limited in the way it is.

684. The demonstration can be expressed and summarised as a sufficient refutation of Berkeley's idealism in the following propositions.

1. Everything that occurs in our feeling is a fact.
2. In sensations and corporeal feelings (corporeal is used to determine the feelings, and may be taken here as an arbitrary sign), we experience in our feeling an action of which we are not the cause; we experience an energy, a force different from ourselves, at work in us.
3. This energy, or felt force, conceived intellectually, is the idea of an ens. Our understanding, through the necessary principle of substance (cf. 583 ss.), conceives this energy as really existing.
4. Such energy is real and limited; consequently, because the conceived ens is only the same energy considered in its existence which we conceive as precise and isolated, it too is real and limited.
5. This limited ens which we call 'body' is not the sentient subject (myself), nor can it in any way be God, whose idea embraces that of an infinite being.
6. Body, therefore, a limited substance and proximate cause of our sensations, exists.
As far as I can see, all these propositions are irrefutable and form part of human common sense.

685. I think it will be helpful if I further explain how Berkeley's individual sense failed to follow the wide road of common sense and fell into error.
Before Berkeley, Locke had placed the source of ideas in sensation and reflection. But his ignorance of the nature of reflection led him to describe it in such a way that it could be easily confused with sensation [App., no. 23]. According to him, reflection could not furnish us with the idea of substance.

As a result, the first step taken by Locke's philosophy in England and France was to suppress reflection and reduce all ideas to one single origin, sense [App., no. 24]. When this is done, substance is an illusion; Hume drew the general conclusion; Berkeley restricted his attention to corporeal substances.

But if Berkeley considered only senses, what was his idea of bodies? His definition is: 'Sensible things therefore are nothing else than so many sensible qualities or combinations of sensible qualities'.(109) He confused sensible qualities with sensations. Granted this, it was easy to show that 'sensible things are in us as modifications of ourselves' because sensations certainly have this condition.

Berkeley's idealism denied corporeal substances because its starting point was a philosophy which had removed intelligence from human beings. Leaving them with the senses only, it banished the very faculty with which substances are perceived. It was not idealism therefore that caused scepticism but the principle on which Berkeley's idealism rested and which contemporaneously produced Hume's scepticism. Berkeley's acceptance of these substances was dependent on his remnant of age-old good sense, which is not completely destroyed in a moment.

Substances and causes must be seen as separate things in Berkeley's mind, like our own prejudgments made without proof or unconnected with our other principles. Substances and causes cannot be explained in any way by his philosophy.
Whatever the truth of this, Berkeley denied the substance of bodies. Nevertheless, he knew through the principle of cause that sensations must be given a cause, which for him was God. In philosophy substance and cause enjoy the same state and, as I said, Berkeley's approach was incoherent.

686. He erred therefore in removing the proximate cause of sensations and turning to the ultimate cause. God is indeed the ultimate cause of all that is and happens, and in this sense God is also the cause of sensations. But the word 'body' was not coined to mean the ultimate cause, and philosophers want to know the proximate not the ultimate cause of sensations.
If our investigation is restricted to this particular philosophical problem, we come to the two results mentioned above: 1. bodies exist, and 2. they are the proximate cause of our sensations. This will receive greater light from the following considerations.

687. In order to know if corporeal substances exist, we must first recall the definition of substance. As we have said, substance is 'something capable of being conceived intellectually with some first conception of ours.'(110) Note that the definition contains the following implications.

1. In order that something be a substance, it does not have to exist independently of every other thing. If that were the case, there would be no created substances because they exist only in dependence on the first cause. For something to be worthy of the name 'substance', it is sufficient for us to be able to conceive it by itself, separate from its first cause. Although it cannot exist totally of itself, it has its own proper existence which enables it to be thought by us in isolation from everything else; its first concept contains no extraneous element.

2. Consequently, a thing can be called 'substance' even if we have to rely on knowledge of something else, such as its cause, in reasoning to its existence or in understanding it completely. As we have said, although nothing can be understood without knowledge of its ultimate cause, this does not prevent us from calling it substance. A first mental conception can be formed of the thing without further need of anything; it can be seen of itself with our first intuition and thought. In a word, its first concept is independent of every other concept; it presents itself as an incommunicable essence, so to speak, mentally distinct from other essences.
We have already noted that if we give to the word 'substance' a more extensive meaning than that granted by common usage, we open the way to false reasoning and countless errors.

688. Bodies, therefore, are substances from the moment they can be conceived by us with our first mental conception as separate and isolated things that cannot be confused with our spirit, with God or with anything else. Accidents, on the other hand, are such that they cannot be conceived with our first intellectual conception as isolated, but only in dependence upon some other ens in which they exist or to which they belong. This is not the case with bodies whose perception, as we have seen, terminates in them without need of anything further (cf. 515-516).

689. This was Berkeley's mistake. He did not analyse sensation carefully. As a result he did not distinguish its two elements: 1. the force acting in us (relative to which we are passive), common to all species of sensation; 2. the various terms and effects of this force, that is, the various sensations. We experience both the force and its different effects, but while we feel the former equally in all sensations, the effects are felt differently according to the variety of means and bodily organs in and through which the force acts upon us. But if the variety of terms and effects of this force (the sensations in so far as they vary amongst themselves) cannot be conceived without the force that produces them, this in its turn cannot be thought without the ens which operates (through the principle of knowledge) (cf. 536, 483-485). Thus we arrive at substance, because that which constitutes an ens is called a substance.

690. We can now sum up all that we have said about the origin of our ideas of bodies.

1. We attain the perception of bodies with the act by which we judge that bodies exist (cf. 528).

2. Analysing this perception, we find it made up of two elements:
a) judgment on the subsistence of a body, and
b) the idea of the same body.

3. Analysing the idea of body, we find it made up of three elements:
a) the idea of existence - we cannot conceive anything, including bodies, without thinking their existence;
b) the primary determination of the idea of existence - this is the essence (the abstract, specific essence) of the thing; in the idea of body it is necessary to think, besides the idea of existence, the term in which the act of existence necessarily terminates, that is, the force or energy at work in all our sensations;
c) the secondary determinations, or sensible qualities - these are the various capacities into which the single force is resolved for producing different sensations.

4. We conceive the three elements of the idea of body in the following way:
a) The idea of being is present naturally in our spirit.
b) When considered in isolation from the variety of sensations we experience, the energy at work in us producing sensations is a mental abstraction (an abstract, specific essence); but, in so far as it acts on us, is known through our interior consciousness - in this respect, consciousness, because it reveals its own passivity equally in every kind of sensation, could be called a 'common sense'.
c) Finally, sensations are provided for me by the exterior sensories.

I have within me, therefore, all the faculties necessary to explain the origin of the perception and idea of body. I have: 1. the faculty that continually beholds being (the intellect), the first element of the idea of body; 2. the faculty (a 'common sense') that perceives a force at work on me which is not myself, and which therefore forms the essence of body, the second element in the idea of body; 3. the five exterior sensories that perceive sensations, the third element in the idea of body; and finally, 4. the faculty of primal synthesis, or judgment, with which I judge as subsistent what I think in the idea of body.

691. Having established the faculties enabling us to perceive the individual elements composing our intellectual perception of bodies, we now have to explain how we unite these elements.
First of all, our various sensations and the energy at work on us are bound together naturally in such a way that we have to make use of abstraction if we wish to have and to think this energy separate from its particular term, that is, from one or other of the sensations. Because energy is the sensation itself considered in its general concept of action done on us and not by us, it cannot be perceived without sensation. Sensation itself, taken whole and entire as it exists in our feeling, that is, as the feeling of a determinate action, is what we have called elsewhere corporeal sense perception.

We now unite corporeal sense perception with the idea of ens in all its universality through the principle of knowledge, which includes the principle of substance. We do this for the first time through the act with which we judge that a body subsists, that is, the intellective perception of body. This act may be described briefly as follows: we are intelligent; as such, we perceive all things as they are, as entia, when they act on us; the bodily force corresponding to the essence of bodies acts on us(111) so that we perceive it as subsisting; this is the perception of bodies.
We have given a general description of the formation of ideas of body. We still have to describe how we perceive our own and other bodies.

(107) As we said, these definitions depend upon the meaning given to the word 'body' by common usage.

(108) This is explained more clearly in App., no. 22.

(109) Dial. 1. - Condillac gives the same definition.

(110) This characteristic is relative to our mind, but founded in the nature of the thing. The other definition I have given regards the thing itself: 'Substance is that through which an ens is what it is', or 'Substance is the abstract, specific essence of an ens considered in relationship to its full, specific essence'.

(111) As a result, the feeling we experience of bodies is a substantial feeling, an immediate action of bodies upon us, which allows us to use the word perception for the first knowledge we acquire of bodies.