While in the field of chemical facts generation marks the highest point of molecular chemistry, in the psychological field love reaches the loftiest summits of the ideal. Love is the force of forces; it makes its appearance when man is strongest; it vanishes when age has weakened him. Love is the joy of joys, it is at the bottom of every desire, of all riches, on every horizon of pleasure; it is always the highest aim. If we except men who were born without gentle feelings, in every human sky love is the brightest star; it is the sun of every firmament. It is the strongest, the most human, the richest of passions. In all forms of generation, whether agamous or sexual, by scission or by endogenesis, whether we consider the son in comparison with the father, or with far Adam, we behold the generated preserve a part of the last or of the first generator, so that the motion communicated from the first to the last generation is transmitted without interruption. Take as the starting-point the Adam of the Bible or the Adam of progressive evolution, the clay breathed into by a God or the Darwinian _ascidia_: each one of us has still within himself a material part belonging to the first man or first father of all men, so that an immense brotherhood unites all living beings. To the divination of the poet who, beholding the flowery meadows, the forests, the swarming of animals, cries out with emotion: "O Mother Nature!" science answers in accord, as it contemplates a quantity of matter and a quantity of life pass from one to the other of those organisms called individuals. For every life extinguished a new life is born, and within us, who occupy the loftiest place among all the living beings on this planet, quiver and vibrate the molecules which have passed through thousands and thousands of existences and thousands and thousands of loves.