d Hygiene.=--Morality is intimately connected with
hygiene, and wherever there appears to be a contradiction between
hygiene and ethics this is due to the fact that individual hygiene has
only been considered, and not public or social hygiene--that is the
hygiene of the race. It is the duty of the medical profession to place
social above individual hygiene, to subordinate the hygienic welfare
of the individual to that of society. A contradiction may exist
between individual morality and hygiene, never between social morality
and hygiene.

=Definition of Morality.=--How can we define morality or ethics?
Liberated as far as possible from all hypothesis, ethics is
theoretically the study of what is good or bad in human actions, and
practically, as regards morality, the duty of doing good and avoiding
evil. But this is hardly explicit, for what do we understand by good
and evil? Not only do some consider good what others consider evil,
but the words which Goethe puts into the mouth of the devil (in
"_Faust_")--that while wishing evil he often did good--will always be
true. This gives a faithful representation of the deplorable want of
adaptation which exists between the good and evil effects of our
actions on the one hand, and the goodness or wickedness of our motives
on the other hand. The inverse is also true, for good intentions often
have evil results. We must, therefore, carefully distinguish between
the ethical motives of the good and bad effects of an action.

If we continue our analysis we shall discover that the same action may
be good for one and bad for another. When a wolf devours a lamb, it is
good for the wolf but bad for the lamb. We cannot live without
destroying other lives, animal or vegetable. The money we earn comes
out of the pockets of others without their always obtaining a
corresponding profit, and so on. Morality is thus _relative_, and we
have not the faculty of discovering anything which is absolutely good
or absolutely bad in itself.

All that men can expect by mutual exchange of their wisdom and good
will is to do as little evil and as much good as possible, that is to
say, to diminish the amount of their physical and psychic ills by
improving their mutual conditions of existence, and thus increasing
the amount of good. Even this is only possible by limiting the ideas
of good and evil almost exclusively to humanity, trampling on the
conditions of existence and the development of other beings,