I.
The first period is that of protoplasmic, vital, organic pre-conscious sensibility. We know that the organism has its memory; it preserves certain impressions, certain normal or morbid modifications; it is capable of adaptation: this point has been well established by Bering (who had been preceded by Laycock and Jessen). It is the outline of the superior form of psychic conscious memory. In the same way there exists an inferior unconscious form—organic sensibility—which is the preparation and the outline of superior conscious emotional life. Vital sensibility is to conscious feeling what organic memory is to memory in the ordinary sense of the word.
This vital sensibility is the capacity to receive stimuli and to re-act to them. In a well-known memoir, now of ancient date,[[2]] Claude Bernard wrote: “Philosophers generally only know and admit conscious sensibility, that which their ego bears witness to. It is for them the psychic modification, pleasure or pain, determined by external modifications.... Physiologists necessarily place themselves at another point of view. They have to study the phenomenon objectively, under all the forms which it puts on. They observe that at the moment when a modifying agent acts on man, it not only provokes pleasure and pain, it not only affects the soul: it affects the body, it determines other re-actions besides the psychic re-actions, and these automatic re-actions, far from being an accessory part of the phenomenon, are on the contrary its essential element.” Then he showed experimentally that the employment of anæsthetics, pushed to an extreme, first abolished conscious sensibility, then the unconscious sensibility of the intestines and glands, then muscular irritability, finally the lively movements of the epithelial tissue. In the same way among plants: under the influence of ether the sensitive plant loses its singular properties, seeds cease to germinate, yeast to ferment, etc. Whence follows the conclusion that sensibility resides, not in the organs or tissues, but in their anatomical elements.
Since then these investigations into protoplasmic sensibility have been pursued with much ardour among micro-organisms. These beings, sometimes animal, sometimes vegetable, are simple masses of protoplasm, generally monocellular, appearing homogeneous, without differentiation of tissues. Now very varied tendencies have been found among these organisms. Some seek light, others flee from it persistently. The protoplasmic mass of myxomycetes which live in the bark of the oak, if placed in a watch-glass full of water, remain there in repose; but if sawdust is placed around them they immediately emigrate towards it as if seized by home-sickness. The actynophrys acts in the same way with regard to starch. Bacteria can discover even the trillionth part of a milligram of oxygen in a neighbouring body. Certain sedentary ciliated creatures appear to choose their food. Some also have thought that they detected an elective tendency in the movement which draws the male ovule towards the female ovule. I have only recalled a few of the many facts which have been enumerated.
If it is necessary to mention other examples, I may refer to the case studied in our own days under the name of “phagocytosis.” The struggle for life goes on, not only among individuals, but also among the anatomical elements which constitute the individual. Every tissue—muscular, connective, adipose, etc.—possesses phagocytes (devouring cells), of which the duty consists in devouring and destroying old or enfeebled cells of the same kind. Besides these special phagocytes there are general phagocytes, such as the white corpuscles of the blood, which come to the help of the others when they are not equal to their task. They stand against the pathogenic microbes, waging upon them an internal struggle, and opposing the invasion of infectious germs. This apparently teleological property seems at first very surprising. Later investigations have shown that the phagocytes are endowed with a sensibility (called chemiotaxic), owing to which they are able to distinguish the chemical composition of their environment and to approach it or leave it accordingly; deteriorated tissues attract certain of them which incorporate the feeble or dead cells, while the healthy and vigorous elements are perhaps able to defend themselves by secreting some substance which preserves them from phagocytosis.
These facts, taken from among many others to which I shall again have to refer when dealing with the sexual instinct, have been interpreted in two very different ways: one psychological, the other chemical.
For some there is in all these phenomena a rudiment of consciousness. Since the movements are adapted and appropriate, varying according to circumstances, there must be choice they say, and choice involves a psychic element; the mobility is the revelation of an obscure “psyche” endowed with attractive and repulsive tendencies.
For the others (whose opinion I adopt), the whole may be explained on physico-chemical grounds. No doubt there is affinity, attraction and repulsion, but only in the scientific sense; these words are metaphors derived from the language of consciousness which should be purged of all anthropomorphic elements. Several authors have shown by numerous observations and experiments the chemical conditions which determine or prevent this pretended choice (Sachs, Verworn, Löb, Maupas, Bastian, etc.).
On this point, as on all questions of origin, we must decide according to probabilities, and the probabilities appear to be all in favour of the chemical hypothesis. In any case, this matter has only a secondary interest for us here. If we admit conscious tendencies, then the origin of the emotional life coincides with the very origin of physiological life. If we eliminate all psychology, there still remains the physiological tendency, that is to say the motor element, which in some degree, from the lowest to the highest, is never quite wanting.
This excursion into the pre-conscious period—since we so regard it—puts us in possession of one result. At the end of this investigation we find two well-defined tendencies, physico-chemical and organic—the one of attraction, the other of repulsion; these are the two poles of the life of feeling. What is attraction in this sense? Simply assimilation; it blends with nutrition. With sexual attraction, however, we must note that we already reach a higher grade; the phenomenon is more complex, the monocellular being no longer acts to preserve itself but to maintain the species. As to repulsion, we may remark that it is manifested in two ways. On one side it is the opposite of assimilation: the cell or the tissue rejects what does not suit it. On another side, at a somewhat superior stage, it is in some degree already defensive.
We have thus gained a basis for our subject by finding that beneath the conscious life of feeling there exists a very low and obscure region, that of vital or organic sensibility, which is an embryonic form of conscious sensibility and supports it.