"Given a psychological state, that part of the state which admits of play, the part which would be translated by an attitude of the body or by bodily actions, is represented in the brain; the remainder is independent of it, and has no equivalent in the brain. So that to one and the same state of the brain there may be many different psychological states which correspond, though not all kinds of states. They are psychological states which all have in common the same motor scheme. Into one and the same frame many pictures may go, but not all pictures. Let us take a lofty abstract philosophical thought. We do not conceive it without adding to it an image representing it, which we place beneath.
"We do not represent the image to ourselves, again, without supporting it by a design which resumes its leading features. We do not imagine this design itself without imagining and, in so doing, sketching certain movements which would reproduce it. It is this sketch, and this sketch only, which is represented in the brain. Frame the sketch, there is a margin for the image. Frame the image again, there remains a margin, and a still larger margin, for the thought. The thought is thus relatively free and indeterminate in relation to the activity which conditions it in the brain, for this activity expresses only the motive articulation of the idea, and the articulation may be the same for ideas absolutely different. And yet it is not complete liberty nor absolute indetermination, since any kind of idea, taken at hazard, would not present the articulation desired.
"In short, none of the simple concepts furnished us by philosophy could express the relation we seek, but this relation appears with tolerable clearness to result from experiment."
The same analysis of facts tells us how the planes of consciousness, of which I spoke just now, are arranged, the law by which they are distributed, and the meaning which attaches to their disposition. Let us neglect the intervening multiples, and look only at the extreme poles of the series.
We are inclined to imagine too abrupt a severance between gesture and dream, between action and thought, between body and mind. There are not two plane surfaces, without thickness or transition, placed one above the other on different levels; it is by an imperceptible degradation of increasing depth, and decreasing materiality, that we pass from one term to the other.
And the characteristics are continually changing in the course of the transition. Thus our initial problem confronts us again, more acutely than ever: are the forms of number and space equally suitable on all planes of consciousness?
Let us consider the most external of these planes of life, and one which is in contact with the outer world, the one which receives directly the impressions of external reality. We live as a rule on the surface of ourselves, in the numerical and spatial dispersion of language and gesture. Our deeper ego is covered as it were with a tough crust, hardened in action: it is a skein of motionless and numerable habits, side by side, and of distinct and solid things, with sharp outlines and mechanical relations. And it is for the representation of the phenomena which occur within this dead rind that space and number are valid.
For we have to live, I mean live our common daily life, with our body, with our customary mechanism rather than with our true depths. Our attention is therefore most often directed by a natural inclination to the practical worth and useful function of our internal states, to the public object of which they are the sign, to the effect they produce externally, to the gestures by which we express them in space. A social average of individual modalities interests us more than the incommunicable originality of our deeper life. The words of language besides offer us so many symbolic centres round which crystallise groups of motor mechanisms set up by habit, the only usual elements of our internal determinations. Now, contact with society has rendered these motor mechanisms practically identical in all men. Hence, whether it be a question of sensation, feeling, or ideas, we have these neutral dry and colourless residua, which spread lifeless over the surface of ourselves, "like dead leaves on the water of a pond." ("Essay on the Immediate Data," page 102.)
Thus the progress we have lived falls into the rank of a thing that can be handled. Space and number lay hold of it. And soon all that remains of what was movement and life is combinations formed and annulled, and forces mechanically composed in a whole of juxtaposed atoms, and to represent this whole a collection of petrified concepts, manipulated in dialectic like counters.
Quite different appears the true inner reality, and quite different are its profound characteristics. To begin with, it contains nothing quantitative; the intensity of a psychological state is not a magnitude, nor can it be measured. The "Essay on the Immediate Data of Consciousness" begins with the proof of this leading statement. If it is a question of a simple state, such as a sensation of light or weight, the intensity is measured by a certain quality of shade which indicates to us approximately, by an association of ideas and thanks to our acquired experience, the magnitude of the objective cause from which it proceeds. If, on the contrary, it is a question of a complex state, such as those impressions of profound joy or sorrow which lay hold of us entirely, invading and overwhelming us, what we call their intensity expresses only the confused feeling of a qualitative progress, and increasing wealth. "Take, for example, an obscure desire, which has gradually become a profound passion. You will see that the feeble intensity of this desire consisted first of all in the fact that it seemed to you isolated and in a way foreign to all the rest of your inner life. But little by little it penetrated a larger number of psychic elements, dyeing them, so to speak, its own colour; and now you find your point of view on things as a whole appears to you to have changed. Is it not true that you become aware of a profound passion, once it has taken root, by the fact that the same objects no longer produce the same impression upon you? All your sensations, all your ideas, appear to you refreshed by it; it is like a new childhood." (Loc. cit., page 6.)