"Thus, whatever may be our kind of nourishment, our body, kept repaired, developed by the absorption of molecules acquired by respiration and alimentation, is really but a current incessantly renewed by means of this assimilation,—directed, governed, and organized by the immaterial force which animates us. To this force we may assuredly give the name of 'soul.' It groups the atoms which suit it, eliminates those which are useless to it, and, starting with an imperceptible speck, an indiscernible germ, ends by building up the Apollo Belvidere or the Venus of the Capitol. Phidias is but a coarse imitator, compared to this hidden and mysterious force. Mythology tells us that Pygmalion became the lover of a statue of his own creation. Not so! Pygmalion, Praxiteles, Michael Angelo, Benvenuto, and Canova created nothing but statues. The force that can construct the living body of man and woman is more sublime.
"But this force is immaterial, invisible, intangible, imponderable, like the attraction which lulls the worlds in the universal melody; and the body, however material it may seem to us, is in itself only a harmonious grouping, formed by the attraction of this interior force. So you see that I confine myself strictly within the limits of positive science in speaking of this young girl by the title of a soul clothed with air,—like you or me, for instance, neither more nor less.
"From the origin of humanity down to within a century or two, it has been believed that sensation was perceived at the very point where it was felt. A pain felt in the finger was considered as having its seat in the finger itself. Children and many people believe so still. Physiology has demonstrated that the impression is transmitted from the finger-tip to the brain by means of the nervous system. If the nerve is cut, the finger may be burned with impunity; the paralysis is complete. We have been able to determine the time taken by the impression in transmitting itself from any part of the body to the brain, and it is known that the rapidity of this transmission is about twenty-eight metres per second. Since then we have referred sensation to the brain. But we have stopped half way.
"The brain is matter, like the finger, and by no means fixed and stable matter. It is essentially changing matter, rapidly variable, and forming no identity. A single lobe, a single cell, a single molecule which does not change, does not and could not exist in the whole mass of encephalic matter. A stoppage of motion, of circulation, or of transformation would be a death-warrant. The brain subsists and feels, only on condition of submitting, like all the rest of the body, to the incessant transformations of organic matter which constitute the vital circuit.
"So it cannot be that our personality, our identity, lies in a certain grouping of cerebral matter,—our individual me, our ego which acquires and preserves a personal scientific and moral value, increasing with study; our ego which feels itself responsible for its acts performed a month, a year, ten, twenty, fifty years ago, during which time however the molecular grouping has been changed frequently.
"Physiologists who affirm that the soul does not exist, are like their ancestors who affirmed that they felt pain in their finger or their foot. They are a little less far from the truth, but they stop on the way when they stop at the brain, and make the human being consist of cerebral impressions. This hypothesis is all the less excusable because these same physiologists know perfectly well that personal sensation is always accompanied by a modification of substance. In other words, the ego of the individual only continues when the identity of its matter ceases to continue.
"Our principle of sensibility, then, cannot be a material object; it is put in communication with the universe by cerebral impressions, by the chemical forces disengaged in the encephalon in consequence of material combinations. But it is different.
"And our organic constitution is perpetually transformed under the direction of a psychic principle.
"Some molecule now incorporated in our organism escapes from it by expiration, perspiration, etc., to belong to the atmosphere for a longer or shorter time, then to be incorporated into another organism,—plant, animal, or man. The molecules which actually constitute your body were not all made part of your person yesterday, and none of them were there three months ago. Where were they? Either in the air or in another body. All the molecules now forming your organic tissues, your lungs, your eyes, your brain, your legs, etc., have already served to form other organic tissues. We are all resuscitated dead men, made from the dust of our ancestors. If all the people who have lived up to this time arose from the dead, there would be five of them to every square foot upon the surface of all the continents,—obliged to climb on one another's shoulders in order to stand; but they could not all be completely resuscitated, for many of the molecules have served successively for several bodies.
"Our own organisms likewise, resolved into their ultimate particles, will help to form the bodies of our descendants.