under the circumstances is not thought of.

The only time when we do recognize what we call "common humanity" is in
extreme cases, matters of life and death; when either man or woman is
expected to behave as if they were also human creatures. Since the
range of feeling and action proper to humanity, as such, is far wider
than that proper to either sex, it seems at first somewhat remarkable
that we have given it so little recognition.

A little classification will help us here. We have certain qualities in
common with inanimate matter, such as weight, opacity, resilience. It
is clear that these are not human. We have other qualities in common
with all forms of life; cellular construction, for instance, the
reproduction of cells and the need of nutrition. These again are not
human. We have others, many others, common to the higher mammals; which
are not exclusively ours--are not distinctively "human." What then are
true human characteristics? In what way is the human species
distinguished from all other species?

Our human-ness is seen most clearly in three main lines: it is
mechanical, psychical and social. Our power to make and use things is
essentially human; we alone have extra-physical tools. We have added to
our teeth the knife, sword, scissors, mowing machine; to our claws the
spade, harrow, plough, drill, dredge. We are a protean creature, using
the larger brain power through a wide variety of changing weapons. This
is one of our main and vital distinctions. Ancient animal races are
traced and known by mere bones and shells, ancient human races by their
buildings, tools and utensils.

That degree of development which gives us the human mind is a clear