The times., 1900-12-23
NoHG the great and fertile scicn- I

certainly take its place in the front rank
As a partial explanation 0or no complete
explanation is possible to finite intel
iigeuce) Of the phenomena of nature it IL
Eliminates every department Of science,
from the study of the most remote cosmic
phencmena accessible to Us to that of the
1ninutsst organisms revealed by the most
powerful microscopes; while upon the
great problem of the mode OF origin Of the
various forms of lifelong considered in
soIuble-it throws 50 clear light that
to many biologists it seems to afford as
complete a solution, in principle, as We
can expect to reach.
THE NATURE AND LIMITS OF EVOLUTION.
So many of the objections which are
still made to the theory OF evolution, and
especially 10 that branch of it which deals
with living organisms. rest upon a mis-
conception of what it processes to ex-
plain. ard even of what any theory can
possibly explain. that q few words n its
nature and limits seem to be necessary.
Evolution, as general principle. i'm
plies that all things in the universe as
we see them have arisen from ether
things which preceded them by a process
of modification, under the action CT Ih3se
aIl-prevailing hut mysterious agencies
known to US as natural forces. or more
generally the laws of nature" More
particuIarIy the term evolution implies
that the process is an 'unrollins" or "un-
folding" derived probably from the way
in which leaves and flowers are usually
rolled up or crumpled up in the bud and
grow into their perfect form by unrolling
or unfolding Insects in the pupa and
veterbrates in the embryo exhibit
somewhat similar condition of folding.
and the word is therefore very applicable
TO an extensive range Of phenomena; but
it must not be taken as universally ap-
plicable, since in the material world there
are other modes OF orderly change unGer
natural laws to which the terms develop
ment or evolution are equally applicable.
The continuity OF physical phenomena
as illustrated by the late Sir William
Grove in 1856 has the same general mean
ing. but evolution implies more than mere
continuity or uccession-something like
growth or definite change from form to
form under the action of Interchangeable
laws.
The point to be especially noted here is
that evolution, even if it Is essentially a
true and complete theory of the universe.
can Only explain the existing conditions
OF nature by showing that it has been de-
rived from some pre-existing condition
through the action of known forces and
y. n f-h .a-
billy Of a similar derivation from a still
earlier condition; but the further back
we 20 the more uncertain must be cur
conclusions, while We can never make any
real approach to the absolute beginnings
OF things Herbert Spencer. and Tany
ether thinkers before him. have shown that
if We try TO realize the absolute nature OF
the simplest phenomena We are inevitably
landed either in a contradiction or in some
unthiDkable proposition. THIS, suppose
We ask. IS matter infinitely diyisible or is
# not? If We say it is, we cannot think
it out. since all infinity, however It may
be stated in words, Is really unthinkable.
II We say there IS a liGit-the ultimate
atom-then, as all size is comparative, We
can imagine q being to whom this atom
seems as large as an apple or even a
house does to US; and we then find it
quite unthinkable that this mass Of matter
should be in its nature absolutely iudi-
visible even by an infinite force. It follows
that all explanations OF phenomena can
only be partial explanations. They can in
form Us Of the last change or the last Sc
ries Of changes which brought about the
actual conditions now existing, and they
cal of,en enable us to predict future
changes to a limited extent; but both the
Infinite past and the remote future are
alike beyond cur powers. Yet the expla-
nations that the theory of evolution give:
US are none the less real and none the less
important, especially when We coinpare It's
teachings with the wild guesses or the
total ignorance of ;he thinkers OF earlier
ages
THE RISE AND PROGRESS OF THE IpEl
or EVOLUTION.
II We trace. however briefly. the gradua
development of knowledge and specula tior
on this subject. We shall perhaps appre
cfate mora fuHy the advance we have realI!
made during the present century.
The first speculations On the nature ant
source or the phenomena OF the universe
of which we have any knowledge arr
these Of the early Greek philosophers
such as Thales. Ana1imander, Anaxa-
goras, and Empedocles; but as the more
important Of their teachings are en-
bodied. with some approach to system
and With much accteness Of reasoning, il
the great poem OF the Latin author Lu
cre;ius-"on the Nature Of Things
will be sufficient to give a sketch Of hi
main conclusions, making use Of the ex
cellent prssc translation by Mr.. II. A.
Munro, oG Trinity College. Cambridge.
Lucretius had very clear idea OF th'
fndostructibility of matter. He argue
;hat things cannot have come cut C
nothing and be says: "A thing never re
turns TO nothing, but all things after dis
ruption 20 back into the FIRST bodies 0
matter" lie then argues that. as the ac
tuai processes Of growth. decay. and cthe
natural changes are imperceptlhle to us
therefore Mature works by unseel
bodies" lie Justly claims great impor
tancc for the demonstration OF the fac
hat in all matter whatever, howeve
solid and hard 1t may be. there are va
cancies. or. as he expresses it. "Mized u
in all things there is void or empt
space" He thus anticipated the moderl
doctrine that the molecules of matter
NOT come into actual contact. He the
defines atoms thus: FIRST. bodies or
solid and Without void" and as no,h n
can be produced from nothing h. con
cludcs that these FIRST bodias fatcrls c