The Book of Love

Many years ago I wrote that to live means nutrition and generation, and the deeper I cast the sounding-line into the dark abysses of life, the more I am convinced that this definition faithfully depicts the most striking characteristics of all creatures which, from bacteria to man, come to life, grow and die on the face of our planet. If, however, I wished still further to simplify my idea, reducing life to its simplest and most essential form, I would say without fear of betraying the truth, that to live means to generate.

Every living body is perishable, but before dying it has the power of reproducing the form that has made it capable of living; and that whirlwind which absorbs and rejects, which assimilates new atoms and repels old ones, and which so clearly represents the eternal picture of life in all its manifestations, is also the most faithful representation of every form of generation.

Nutrition is a real genesis, and in the great chemical laboratory of living beings we have at all times before our eyes the reproduction of histological elements of organs and individuals. We lose hair, epithelia, white corpuscles every day; and yet every day we generate hair, epithelia and leucocytes: this is an every-day generation in the body of man. A nail falls off, a new one takes its place: this is the reproduction of an organ. We generate children similar to ourselves: this is the reproduction of an entire organism, the true generation. But in one of our offspring we see re-repeated a mole which is on our nose: this is the reproduction of an organ within an organism. On the other hand, one race generates another race, one species another species; and here we see a broader genesis by which from the reproduction of a cell through another cell we gradually pass to the generating of an organ, of an individual, of a race, of a species.

The world of living beings is a gigantic tree and from its trunk shoot forth the branches of classes, orders, species. On the branches leaves grow, which are the individuals; but each one of these small individuals generates within itself many cells, true organisms within greater ones. The world of living beings is but a great laboratory of prolific, incessant generation. Cells generate cells; organs, organs; species, species. An intimate brotherhood makes us members of one great organism—the placenta of living beings; and among ourselves we exchange the same matter which each of us in turn contributes to the work of apparent destruction, called nutrition, and to that of reproduction, designated as generation. To feed themselves and to generate, living beings are continually exchanging with each other a part of their own matter which, passing from one organism to another, seems to acquire new energy and new life. On the one hand, seaweeds live on mushrooms, carnivorous animals devour herbivorous, herbivorous feed on herbs, and man, the highest branch of the tree of living beings, partakes of all. On the other hand, males and females in continuous succession interchange part of their matter, remoulding their primitive forms.

The most elementary form of life is not, however, the cell, since at a lower stage we find the protoplasm, the trueprimum vivens which, by scission, generates the individual; and, by nourishing itself, nobody can tell what mysterious genesis of atoms it induces within its own most simple organism. The protoplasm cannot live without a continual exchange of matter, so that the live molecules of yesterday are dead today; and those which are alive today will be dead tomorrow; therefore nutrition also, in the last analysis, is an intimate and very mysterious generation.