Francis Howe Johnson.

God in evolution: a pragmatic study of theology online

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another of our world is touched by its gilding
rays, then all the uplands are illuminated, then
its life-giving beams penetrate to the valleys and
light up its darkest glens. Every lovable thing
in this world is educating us for this experience,
and every lovable thing is transitory for the very
reason that it exists for the purpose of lifting us
into something inexpressibly higher, more satis-
factory, more enduring, than itself.


The Evidential Value of Analogy

ALL our constructive knowledge is condi-
tioned upon one great fact of the universe
that underlies it. Experience has demon-
strated that the universe is, to a very great
extent, a series of modified repetitions, so that an inti-
mate knowledge of any one part of it is, within certain
limits, a true guide to the interpretation of other parts
of it and, progressively, to every part. On this fact
all our analogical thinking hinges; and, so far as elab-
orated knowledge is concerned, all our progress is
dependent upon the use of analogy.

The intellectual process through which our knowl-
edge is continually extending its bounds has three
well denned stages which are interdependent. These
three stages we may call investigation, speculation,

The first and the last of these are the prosaic parts
of knowledge-getting. They have to do with the
actualities of the world, and involve plodding, labor-
ious application to details. The middle term or
stage is, on the contrary, an activity of the imagina-
tive faculty, in the exercise of which, construction is
absolutely unfettered. Like a sorcerer, it makes and
unmakes, builds and destroys without stint. In it
the poetry of the world takes its rise, and inheres.



Without it there would be no enthusiasm in living, no
idealizing, no uplift from the heavy, dull round of
necessary occupation. It is the very soul of art. It
is the solace of our quiet hours; it is also the insti-
gator of all our bravest and noblest endeavours. It
holds us to our purposes, makes us strong in adver-
sity, loyal in the presence of seductions. It is the
faculty by which we transcend ourselves and rise in
the scale of being.

But all its nobler uses are conditioned upon dis-
cipline; that is, upon its working in harness with the
other above-mentioned factors. These two, labouring
on either side, tend to keep it in order while it, in turn,
sends a current of life and inspiration through them,
making the movement toward knowledge, notwith-
standing its drudgery and set-backs, an experience,
on the whole, of joy and ever-increasing delight.

I am not saying that we always consciously apply
these three forms of activity in our conduct of life-
Instinct goes before understanding. Even after we
have accustomed ourselves to reflection, we employ
the three-fold process as if it were no process at all,
and call it sympathy, intuition, divination. And
when, perchance, we do turn our attention to the
nature of our methods and processes, we find these
activities already functioning in perfect order. Every
time we encounter an object that is somewhat strange,
and make an effort to assimilate the new experience
to the established society of our accepted beliefs, we
go through all the three stages. The perception of
it arouses curiosity and the question, what is it?
Instinctively we call before us resemblances that may
suggest a partial answer. This leads to a guess or
hypothesis as to its nature; and then, if we are per-


mitted, we proceed to test the correctness of it by
the sense of touch, or smell, or taste. The continued
use of this process underlies all our organized knowl-
edge. Even that which seems the most directly
given is, in reality, the product of its employment.

To use Mr. G. H. Lewes' expression, every new idea
must be soluble in old experiences, be recognized as
like them; otherwise it will be unperceived, uncompre-
hended. A conception which is novel, or largely
novel, is unintelligible even to the acutest intellect,
It must be prepared for, pre-conceived ; and, by the
exhibition of its points of similarity and attachment
with familiar conceptions, its congruity with these,
may become the ground of its acceptance."*

Except for our own self-consciousness we could
know nothing whatever of self-consciousness or intel-
ligence in others; and, beyond the instinctive stage,
our progressive knowledge of them is attained, first,
by a series of analogical assumptions, or hypotheses,
which may properly be described as prejudices; and,
second, by the verification or correction of these
by further experience. Certain general conclusions
with regard to mankind result from this. First, that
all members of the human race are like ourselves
and like each other; second, that no two members
of the race are like each other; and third, that the
least developed can have only a very limited and im-
perfect knowledge of the most developed. In other
words, experience endorses our use of self-knowledge
as the ground of interpretation for conscious beings
widely separated from us, but, at the same time,
lays upon us the necessity of allowing for wide, blank

* "Mind as a function of the Organism." Sec. 77.


spaces in our conception. The more closely connected
two persons are by birth, training, and temperament,
the fewer the blank spaces, the more complete and
trustworthy the conception formed. Yet those who
are most widely separated find, in virtue of their
common humanity, grounds for a fairly probable
judgment of character.

But this is only the beginning of the analogical use
to which we put our inner knowledge of self. All our
interpretation of the motives of the lower animals
proceeds upon the same principle as our interpreta-
tion of men. In our critical moments we may be
inclined to deny that a shepherd-dog has any commun-
ity of nature with man. But in the synthetical, prac-
tical judgments of his shepherd-master he figures as
a slightly modified human being. I think I may affirm
that our success in dealing with the more intelligent
animals depends upon the faithfulness and discrimi-
nation with which we apply this self-derived analogy.
"Put yourself in his place" is, within certain limits, as
good a maxim for the regulation of our conduct
toward a horse as toward a man.

From the more intelligent animals we descend by
regular gradations till we reach those that are lowest in
the scale of organization. The structure of the appar-
ently brainless ant, with its plurality of co-ordinate
nerve centres, seems at far too great a remove from
the human organism to afford the slightest ground
for a trustworthy analogy. But when we study its
adaptations and modifications of means to ends, we
are, in spite of our knowledge of structure, convinced
that ants not only have something closely resembling
intelligence, but that they have an amazing amount
of it. And when we drop still lower to contemplate


the behaviour of the apparently structureless amceba
in search of its food, we are constrained to apply the
same analogy for the explanation of what we behold.
The inferences we draw are crude, and perhaps in
many respects wide of the truth, but it guides us to-
ward the truth, and is the germ of our conception of

Now, with regard to the threefold process, here
are certain facts; this process is embedded in our
nature, we find it in operation before we reach the
stage of analyzing our mental processes, we have dis-
covered no substitute for it in the conduct of daily
life. These considerations are to my mind the strong-
est possible justification for the belief that this three-
fold method is the one by which all our constructive
knowledge is to be acquired. This is my hypothesis;
and for its endorsement I must make inquiry of the
various departments of human knowledge that have
most grown and prospered, to find out how it has
been with them. Have they found another method
more reliable or shorter or, in general, more satisfac-
tory? The physical sciences, for instance, have they
invented a better way? On the contrary, all their
triumphs in the past have sprung from the use of
the three-stage method and all their hope for the
future is vested in it.


Up to a certain point the labour of science consists
in observation, in prying research for the collection
of a great number of facts; then comes the work of
comparison and classification; then the work of con-
jecture, in which the imagination has free play; then


the process of exclusion, in the course of which many
of the suggestions of fancy are set aside as unworthy
of attention; then the process of verification for the
proof, or disproof, of the surviving conjecture. We
are at present interested in that stage that relates to
the formation of hypotheses.

The scientific imagination is, from the first, held in
partial control by past experiences, which, at the same
time, restrain and furnish it with building material in
the shape of resemblances. Guided by these, it con-
structs an hypothetical explanation of a given group
of phenomena; that is, it finds an analogy. Having,
with the aid of this, ascertained a principle of limited
range, it expands this again by the use of the imagi-
nation, till the same principle is serviceable for a very
much wider class of phenomena. Every time it
repeats this process it acts on the assumption that
the world is a series of modified repetitions: and
every time an hypothesis so made is verified, the
correctness of this assumption receives an additional

The results of science thus present us with what
has been appropriately called a "hierarchy of prin-
ciples." Each partial generalization foreshadows a
higher one in which it is, soon or late, seen to be
comprehended. And what is true of principles is
equally true of groups of phenomena. The whole
science of classification depends upon the fact of rep-
etition, with modification, on different scales.

Comparatively recent discoveries have disclosed
the existence of such orderly arrangements on differ-
ent planes where we should least have suspected it.
Chemistry, as we know, is arrested in its all-dissolving
course by certain elements that seem to defy analy-


sis, — elements that have therefore to be provision-
ally treated as final, absolutely dissimilar substances.
Here, if anywhere, we should anticipate that the
above-mentioned rule would fail us. But, almost
simultaneously by a Russian and a German chemist,
the very remarkable discovery was made that these
elements are capable of being classified in successive

The following very brief and clear statement of
this was given some years ago by Professor Huxley:
— "If the sixty-five or sixty-eight recognized elements
are arranged in the order of their atomic weights,
the series does not exhibit one continuous, progres-
sive modification in the physical and chemical charac-
ters of its several terms, but breaks up into a number
of sections, in each of which the several terms present
analogies with the corresponding terms of the other
series. Thus the whole series does not run —

a, b, c, d, e, f, g, h, i, j, k, etc.

a, b, c, d, — A, B, C, D, — a, ft y, 8, etc.

So that, it is said to express a law of recurrent sim-
ilarities. Or the relation may be expressed in another
way. In each section of the series the atomic weight
is greater than in the preceding section; so that if
w is the atomic weight of any element in the first
segment, w + x will represent the atomic weight of
any element in the next, and w -f x + y the atomic
weight of any element in the next, and so on. There-
fore the sections may be represented as parallel series,
the corresponding terms of which have analogous
properties; each successive series starting with a
body the atomic weight of which is greater than


that of any in

TOCnlATi • ■

the preceding series.

, in the following

lclblilOIl .




w + x





w + x + y

This is a conception with which biologists are very
familiar; animal and plant groups constantly appear-
ing as series of parallel modifications of similar and
yet different primary forms." *

The discovery of this order led the Russian chemist,
Mendelejeff, to indicate the existence of other ele-
ments not hitherto recognized. When he first ranged
the known elements in a tabular form he found that
a symmetrical arrangement left, here and there, vacant
spaces. He called attention to these gaps, and ven-
tured not only to prophesy that elements, then un-
known, would be found to fill them, but even went so
far as to describe in detail what these undiscovered
elements would probably be like. Only a short time
elapsed before the elements thus described were dis-

Other illustrations of this principle, having a closer
relation to our problem, will easily occur to the reader.
If we wish to find an analogy for the assumption
that the exceedingly limited may reveal the nature
of that which is inexpressibly extended, we have only
to call to mind the great law of Newton, — that every
particle of matter in the universe is related to every
other particle as each of the planets is related to the

* "The Advance of Science in the Last Half Century," p. 56.


other heavenly bodies. Following out this law, in con-
nection with the atomic theory, we attain to that
astounding conception for which science has no rebuke,
that a molecule may be a solar system in miniature.
Alluding to such a conception, Professor J. P. Cooke
says: "A theory which assumes that within the masses
of material bodies the motions of suns and systems
are reproduced on a scale so minute as to task our
power of imagination to grasp the conception, is found
to be in complete accordance with all the facts which
can be observed." *

But there is another aspect of our hypothesis that
needs illustration. The simplicity of the relations
above instanced may seem to separate them by a
wide difference from the relations postulated for the
interpretation of the inner reality of living things.
But even here we are not without a precedent in
the methods of science. The marvel of marvels for
condensed potentiality is the egg. For in it, by the
aid of the microscope, we may trace the whole pro-
cess of the creation of a higher animal. First we
have the germ, a nucleated cell. This becomes two
by a division of itself and by growth. By the repeti-
tion of this process it becomes a multitude. The egg
then presents to us an aggregate of homogeneous
cells, capable of being still further multiplied and, at
the same time, modified into a great variety of
classes having different forms and functions. By
these, as by a trained army of artisans, each knowing
just when to go and what to do, the living organism,
that in its unity we call a being, is built up.

Now, in this wonderful process, modern science

* "The Credentials of Science the Warrant of Faith," p. 265.


believes that it has discovered the true key to the
history of the whole animated world. At the begin-
ning of his book on evolution, Dr. Joseph Le Conte
says: "Every one is familiar with the main facts con-
nected with the development of an egg. . . . Now
this process is evolution. It is more, — it is the type
of all evolution. It is that from which we get our
idea of evolution, and without which there would
be no such word." As to the importance of the
principle thus made known to us, the same writer
says: — "The process pervades the whole universe,
and the doctrine concerns every department of
science, — yea, every department of human thought.
It is literally one-half of all science."


Now let us see to what extent this important prin-
ciple, suggested by the egg, rests upon analogy. It
has been reached by the comparison of three separate
series of forms found in nature. First we have the
taxonomic series. This is the result of classifying the
contemporary forms of animal life on a scale of rela-
tive complexity. Beginning with a unicellular organ-
ism, we advance, step by step, till we reach the higher
animals, made up of innumerable cells having a great
variety of forms, functions, and relations. The mem-
bers of this series are not a succession of stages pro-
ceeding one from another, but a series of completed,
independent existences living alongside of each other.

The second series is the phylogenetic, or geological,
series. This seems to be the history in time, of the
former. It shows that the simplest organisms came
into being first, then those somewhat less simple, and


then, successively, those which were more and more
complex. The members of this series do not appear
to be genetically related to each other, any more than
those of the first series, but the arrangement of their
succession in time gives us the idea of a progres-
sive creation. But now we come to the third, the
ontogenetic, or egg, series.

For the purpose of comparison, the process that
takes place in the egg is marked off into a succes-
sion of stages; and the relations which these stages
sustain to each other seem to reveal in a wonderful
manner the secret of the other two series. Like the
taxonomic series, it begins with a single cell, and then,
by the gradual multiplication and differentiation of
cells, it reaches that unified complex of organs — a
higher animal. In this series all the members are gen-
etically related, that is, they are stages of being that
proceed directly the one from the other.

This seems to explain the geological, or historical,
series, because its members are similarly related to
each other, both in the order of time and in the order
of complexity. And it seems to explain the classi-
fication series, and to unite this with the historical,
by showing how a series that has been progressive in
time may, in its results, present the aspect of an aggre-
gate of unprogressive, fixed forms. For the egg
series, although progressive, gives rise all along its
course, to forms that remain as immovably fixed as
the different species of animals that we see around
us. Different classes of cells, as we have seen, are
evolved; and although some of these give rise to new
classes, some of them remain to represent the partic-
ular phase of the organism that they introduced.
The same is true of organized groups of cells. There


is a continual branching and re-branching. But, in
the completed organism, the various stages of differ-
entiation continue to be more or less represented by
classifiable cells and groups of cells.

More remarkable still do these coincidences appear
when it is further observed that the earlier stages of
the egg series of a higher animal bear a striking resem-
blance to the more mature stages of lower animals.
This is perhaps most clearly illustrated by a compari-
son of the successive embryonic stages of the human
brain with the mature brain of animals lower in the
scale. The first observable form is less elaborate than
that of the ordinary fish. In the next stage it resembles
that of a fish; then, by the relative increase of the
cerebrum, it reaches the reptilian stage; by continued
growth it partly covers the optic lobes and resembles
the brain of a bird; then it wholly covers the optic
lobes and, partially overspreading the cerebellum and
the olfactory lobes, may be called a mammalian brain;
and finally it covers and overhangs all and becomes
a human brain. In view of these facts, Dr. Le Conte
sums up the argument for evolution as follows : —

"Now, why should this peculiar order be observed
in the building of the individual brain? We find the
answer — the only conceivable answer — to this question
in the fact that this is the order of the vertebrate
brain by evolution throughout geological history.
We have already seen that fishes were the only verte-
brates living in Devonian times. The first form of
brain, therefore, was that characteristic of that class.
The reptiles were introduced; then birds and mar-
supials; then true mammals; and, lastly, man. The
different styles of brain characteristic of these classes
were, therefore, successively made by evolution from


earlier and simpler forms. In phylogeny, this order
was observed because these successive forms were
necessary for perfect adaptation to the environment
at each step. In taxonemy we find the same order,
because, as already explained, every stage in advance
in phylogeny is still represented in existing forms.
In ontogeny we have still the same order, because
ancestral characteristics are inherited and family
history recapitulated in the individual history." *

When presented in this form, the reasoning that
connects the egg series with the other two does not,
at first sight, seem to rest altogether upon analogy.
But a close inspection of the argument will, I think,
convince us that it has very little else to support it.
The order of the thought seems to be this: first we
compare the three series and find a close resemblance
in the succession of their stages; second, knowing
that the stages in the egg series are genetically related
to each other, we infer that those of the geological
series are similarly related; third, by a reflex argument,
we infer that the reason why the members of the
egg series are genetically related is found in the fact
that those of the geological series were, previously,
so related.

Now, aside from analogy, what support do we get
for the first inference? If investigation showed that
similar conditions affected the two series, we could
at once establish our inference on the principle that
like causes produce like effects. But this is not the
case. The conditions in the one situation have no
resemblance to the conditions in the other; at least
they have no resemblance to the conditions that are

* "Evolution and its Relations to Religious Thought,"
p. 150.


adduced as the chief cause of the original order. Con-
flict with, and adaptation to, environment are said to
have had a large share in the origination of the race
series. But the environment of the individual em-
bryo is, in every respect, unlike that of the unpro-
tected militant organism. In reasoning from the egg
series to the geological, therefore, we have nothing to
go upon but analogy; that is, a similarity of order
existing under external circumstances that are quite

Let us examine the second step. Having analog-
ically made the hypothesis that the members of the
geological series are genetically related, how are we
justified in assigning this as the cause of the phenom-
ena of the egg series? It is said that the principle
of heredity supplies us with the means of making such
a deduction. But we must further ask, to what ex-
tent does the principle of heredity, as thus applied,
rest upon inference from analogy? The answer must
be, almost entirely. We know nothing about the
principle of heredity, as related to the remote past,
except inferentially and analogically. So far as direct
knowledge of the law of heredity is concerned, it
remains such a mystery from beginning to end, as
to make the exclusion of almost any hypothesis

But the same ignorance of its laws makes it impos-
sible to deduce results with any confidence from it.
The analogies under discussion have contributed
many suggestions about the law of heredity ; but from
the law of heredity, independently of these analogies,
we get very little assistance.

The elder Agassiz, who did so much to prepare
the way for the evolution hypothesis, brought to-


gether and classified the materials in all three of the
above-mentioned series, and, moreover, made it the
great work of his life to demonstrate the close rela-
tionship in which they stood to each other. He even
went so far as to affirm that the observed repetitions
were such as to render the embryonic series a true key
to classification in the other two. But he did not
advance to the position that species are derived from
each other by natural descent, because there was
nothing in the known principles of heredity to compel
such an inference. The connection between the three
series was, for him, one that had its origin in the
mind of the Creator. There was a uniformity of plan
and method, but not an interdependence between the

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Online LibraryFrancis Howe JohnsonGod in evolution: a pragmatic study of theology → online text (page 19 of 22)