The Evolution of Man, vol 1 | Page 7

CHAPTER 1.
1. THE FUNDAMENTAL LAW OF ORGANIC EVOLUTION.
The field of natural phenomena into which I would introduce my
readers in the following chapters has a quite peculiar place in the broad
realm of scientific inquiry. There is no object of investigation that
touches man more closely, and the knowledge of which should be more
acceptable to him, than his own frame. But among all the various
branches of the natural history of mankind, or anthropology, the story
of his development by natural means must excite the most lively
interest. It gives us the key of the great world-riddles at which the
human mind has been working for thousands of years. The problem of
the nature of man, or the question of man's place in nature, and the
cognate inquiries as to the past, the earliest history, the present situation,
and the future of humanity--all these most important questions are
directly and intimately connected with that branch of study which we
call the science of the evolution of man, or, in one word,
"Anthropogeny" (the genesis of man). Yet it is an astonishing fact that
the science of the evolution of man does not even yet form part of the
scheme of general education. In fact, educated people even in our day

are for the most part quite ignorant of the important truths and
remarkable phenomena which anthropogeny teaches us.
As an illustration of this curious state of things, it may be pointed out
that most of what are considered to be "educated" people do not know
that every human being is developed from an egg, or ovum, and that
this egg is one simple cell, like any other plant or animal egg. They are
equally ignorant that in the course of the development of this tiny,
round egg-cell there is first formed a body that is totally different from
the human frame, and has not the remotest resemblance to it. Most of
them have never seen such a human embryo in the earlier period of its
development, and do not know that it is quite indistinguishable from
other animal embryos. At first the embryo is no more than a round
cluster of cells, then it becomes a simple hollow sphere, the wall of
which is composed of a layer of cells. Later it approaches very closely,
at one period, to the anatomic structure of the lancelet, afterwards to
that of a fish, and again to the typical build of the amphibia and
mammals. As it continues to develop, a form appears which is like
those we find at the lowest stage of mammal-life (such as the
duck-bills), then a form that resembles the marsupials, and only at a
late stage a form that has a resemblance to the ape; until at last the
definite human form emerges and closes the series of transformations.
These suggestive facts are, as I said, still almost unknown to the
general public--so completely unknown that, if one casually mentions
them, they are called in question or denied outright as fairy-tales.
Everybody knows that the butterfly emerges from the pupa, and the
pupa from a quite different thing called a larva, and the larva from the
butterfly's egg. But few besides medical men are aware that MAN, in
the course of his individual formation, passes through a series of
transformations which are not less surprising and wonderful than the
familiar metamorphoses of the butterfly.
The mere description of these remarkable changes through which man
passes during his embryonic life should arouse considerable interest.
But the mind will experience a far keener satisfaction when we trace
these curious facts to their causes, and when we learn to behold in them
natural phenomena which are of the highest importance throughout the
whole field of human knowledge. They throw light first of all on the
"natural history of creation," then on psychology, or "the science of the

soul," and through this on the whole of philosophy. And as the general
results of every branch of inquiry are summed up in philosophy, all the
sciences come in turn to be touched and influenced more or less by the
study of the evolution of man.
But when I say that I propose to present here the most important
features of these phenomena and trace them to their causes, I take the
term, and I interpret my task, in a very much wider sense than is usual.
The lectures which have been delivered on this subject in the
universities during the last half-century are almost exclusively adapted
to medical men. Certainly, the medical man has the greatest interest in
studying the origin of the human body, with which he is daily occupied.
But I must not give here this special description of the embryonic
processes such as it has hitherto been