freethinkers, including d’Alembert, Diderot, Holbach, and Voltaire, who first dared to follow the consequences of a mechanistic science—incomplete as it then was—to the rules of human conduct and who thereby laid the founda­tion of that spirit of tolerance, justice, and gentleness which was the hope of our civiliza­tion until it was buried under the wave of homicidal emo­tion which has swept through the world. Diderot was singled out, since to him the words of Lord Morley are devoted, which, however, are more or less characteristic of the whole group.

J. L.

The Rockefeller Institute
for Medical Research,
August, 1916

CONTENTS

The Organism as a Whole

CHAPTER I

INTRODUCTORY REMARKS

1. The physical researches of the last ten years have put the atomistic theory of matter and electricity on a definite and in all probability permanent basis. We know the exact number of molecules in a given mass of any substance whose molecular weight is known to us, and we know the exact charge of a single electron. This permits us to state as the ultimate aim of the physical sciences the visualiza­tion of all phenomena in terms of groupings and displacements of ultimate particles, and since there is no discontinuity between the matter constituting the living and non-living world the goal of biology can be expressed in the same way.

This idea has more or less consciously prevailed for some time in the explana­tion of the single processes occurring in the animal body or in the explana­tion of the func­tions of the individual organs. Nobody, not even a scientific vitalist, would think of treating the process of diges­tion, metabolism, produc­tion of heat, and electricity or even secre­tion or muscular contrac­tion in any other than a purely chemical or physico­chemical way; nor would anybody think of explaining the func­tions of the eye or the ear from any other standpoint than that of physics.

When the actions of the organism as a whole are concerned, we find a totally different situa­tion. The same physiologists who in the explana­tion of the individual processes would follow the strictly physico­chemical viewpoint and method would consider the reac­tions of the organism as a whole as the expression of non-physical agencies. Thus Claude Bernard,1 who in the investiga­tion of the individual life processes was a strict mechanist, declares that the making of a harmonious organism from the egg cannot be explained on a mechanistic basis but only on the assump­tion of a “directive force.” Bernard assumes, as Bichat and others had done before him, that there are two opposite processes going on in the living organism: (1) the phenomena of vital crea­tion or organizing synthesis; (2) the phenomena of death or organic destruc­tion. It is only the destructive processes which give rise to the physical manifesta­tions by which we judge life, such as respira­tion and circula­tion or the activity of glands, and so on. The work of crea­tion takes place unseen by us in the egg when the embryo or organism is formed. This vital crea­tion occurs always according to a definite plan, and in the opinion of Bernard it is impossible to account for this plan on a purely physico­chemical basis.