Then disharmony, transformed into harmony, will cause the greatest of ills to disappear.

Faith in the power of Science and in the possibility of modifying human nature itself through Science was the foundation of the optimistic philosophy of his maturity. Thoughts full of strength and hope shine like leading stars all along his philosophical works.

“Alone, Rational Science is capable of showing humanity the true path.”

“The real goal of human existence consists in an active life in conformity with individual capacity; in a life prolonged until the appearance of the death-instinct, and until Man, satisfied with the duration of his existence, feels the desire for annihilation.”

“Man is capable of great works; that is why it is desirable that he should modify human nature and transform its disharmonies into harmonies.”

“If an ideal capable of uniting men in a sort of religion is possible, it can only be founded on scientific principles. And, if it is true, as is often affirmed, that man cannot live without faith, it must be faith in the power of Science.”

Thus Elie Metchnikoff had begun by the study of nascent life in inferior beings; by a logical and continuous chain, he had followed the whole cycle of development of living beings in their continuity and their whole.

From the initial question of intracellular digestion he had reached the most exalted problems which can occupy our minds, the harmonising of human discords through knowledge and will.

Such is the harmonious edifice which he has built.