s already found by science are futile and of
little interest. But science, confident of its methods, has quietly
continued to work. Little by little the answers to some of the
questions that have been set have begun to appear.

Man, because of the fundamental disharmonies in his constitution, does
not develop normally. The earlier phases of his development are passed
through with little trouble; but after maturity greater or lesser
abnormality begins, and ends in old age and death that are premature and
pathological. Is not the goal of existence the accomplishment of a
complete and physiological cycle in which occurs a normal old age,
ending in the loss of the instinct of life and the appearance of the
instinct of death? But before attaining the normal end, coming after the
appearance of the instinct of death, a normal life must be lived; a life
filled all through with the feeling that comes from the accomplishment
of function. Science has been able to tell us that man, the descendant
of animals, has good and evil qualities in his nature, and that his life
is made unhappy by the evil qualities.

But the constitution of man is not immutable, and perhaps it may be
changed for the better. Morality should be based not on human nature in
its existing condition, but on ideal human nature, as it may be in the
future. Before all things, it is necessary to try to amend the evolution
of human life, that is to say, to transform its disharmonies into
harmonies. This task can be undertaken only by science, and to science
the opportunity of accomplishing it must be given. Before it is possible
to reach the goal mankind must be persuaded that science is all-powerful
and that the deeply-rooted existing superstitions are pernicious. It
will be necessary to reform many customs and many institutions that now
seem to rest on enduring foundations. The abandonment of much that is
habitual, and a revolution in the mode of education, will require long
and painful effort. But the conviction that science alone is able to
redress the disharmonies of the human constitution will lead directly to
the improvement of education and to the solidarity of mankind.

The Prolongation of Life

Professor Metchnikoff's volume, on "The Prolongation of Life:
Studies in Optimistic Philosophy," was published in 1907, and is in
some respects the most original of his works. In it he carries much
further the arguments and the studies to w