Origin of Thought

Appendix 14. (708)

When we had to establish the first, substantial difference between our own body and bodies different from our own, we found that the former was perceived along with us as sentient subject, while the latter were perceived simply as forces different from the subject. This difference was proved by: 1. a fact revealed by consciousness — when we say ''fact' we mean ''something self-evident', and therefore ''certain'; 2. use of the theory of perception already outlined (cf. 528-536), and of the principles of substance and cause (cf. 567-569).

However, our body can be perceived extrasubjectively, just like any other body. In this case, if we perceive our body as an extrasubjective term of our sense-faculty, we can discover secondary, but nevertheless important differences, enabling us once again to distinguish it from external bodies. This way of distinguishing our own body, considered as different from us as subject, from external bodies, supposes the truth about an extrasubjective term of our sense-faculty. There was, however, no need of this as long as the distinction between our own and other bodies depended upon the substantial difference between subject andthat which is extrasubjective.

Three differences may be noted between the extrasubjective perception of our own and external bodies. These differences show that our own body is quite distinct from any external body. Galluppi sets out the differences as follows:

First difference. ''If your right hand is hot, and your left cold, and you bring them into contact, you will feel the same ""self" in them both. ""Myself" which feels the heat of the right hand is the same as that which feels the cold of the left. ""Myself", therefore, seems to exist in both hands. But if you touch a block of iron with one hand, you will feel ""myself" in the hand without feeling it in the block of iron. It does not seem to exist in the iron, which is extraneous to ""myself". Contact between the two hands furnishes two sensations; contact with the block of iron only one. ""Myself" looks upon right and left hands as parts of its own body because it has a touch-feeling in both; it looks upon the block of iron as an external body because it has a touch-feeling of the iron, but not in the iron. ""Myself" regards as its own the body which it feels, and in which it seems to feel or to exist; it regards as external to itself a body which it feels, but in which it does not seem to feel or exist.'

Second difference. ''If you want to move your arm, you do so from within, immanently. But the block of iron will not move simply because you want it to. First, you have to move your hand towards it, and then move the block by moving your hand. ""Myself" regards as its own the body which it can move by willing to do so; it regards as external any body whose movement does not depend upon its act of will.'

Third difference. ''You can move the block of iron to a place where it no longer acts upon any of your senses. But you cannot do this with your own body. At least while you are awake, it is impossible to avoid its action. ""Myself" regards as its own, therefore, that body which is unceasingly present to it; it regards as external any body ceasing to modify it or not present to it' (Elementi di filosofia, etc. T. 3, chap. 3, ¦29).

Galuppi concludes from these observations that we can distinguish our own from external bodies by means ofsight andtouch. But both senses perceive extrasubjectively, and I am not satisfied with showing a difference between our own body and external bodies as differing terms of sight and touch. We must also recognise that our own body pertains to ourselves as subject, while external bodies are purely extrasubjective. This is the basic difference beteen them.

Nevertheless, the three facts indicated by Galluppi do help considerably to underline the distinction between a subject and something different from the subject, if we take their analysis one step further. In the first of the three differences, where thehand feels itself as sentient, we find a subject, while the block of iron which is only felt and does not feel itself, is indicative of something different from the subject. In the second difference, the movement that I want to carry out through my hand can be perceived not only with sight and touch, but principally through interior feeling and consciousness, which draw attention to the subject. The movement I impart to the block of iron is clearly noted only through sight and touch indicating something different from the subject. In the third difference, I feel my body united with me wherever I go, not because I see it or touch it, but principally through interior consciousness, which indicates me as itssubject. The distance of external bodies is brought home to me by touch or the other senses indicating that these bodies are extrasubjective terms of my feeling powers.