that of the past of the dependence of thought and feeling on physical
processes; and it may be that the qualities of the mind will be
studied through organic combinations as we now study the character of
a force through the affections of ordinary matter. We believe that
every thought and every feeling has its definite mechanical
correlative--that it is accompanied by a certain breaking up and
remarshalling of the atoms of the brain. This latter process is
purely physical; and were the faculties we now possess sufficiently
expanded, without the creation of any new faculty, it would doubtless
be within the range of our augmented powers to infer from the
molecular state of the brain the character of the thought acting on
it, and, conversely, to infer from the thought the exact molecular
condition of the brain. We do not say--and this, as will be seen, is
all-important--that the inference here referred to would be an _à
priori_ one. But by observing, with the faculties we assume, the state
of the brain and the associated mental affections, both might be so
tabulated side by side that, if one were given, a mere reference to
the table would declare the other. Our present powers, it is true,
shrivel into nothingness when brought to bear on such a problem, but
it is because of its complexity and our limits that this is the case.
The quality of the problem and of our powers are, we believe, so
related, that a mere expansion of the latter would enable them to cope
with the former. Why, then, in scientific speculation should we turn
our eyes exclusively to the past? May it not be that a time is
coming--ages no doubt distant, but still advancing--when the dwellers
upon this fair earth, starting from the gross human brain of to-day as
a rudiment, may be able to apply to these mighty questions faculties
of commensurate extent? Given the requisite expansibility to the
present senses and intelligence of man--given also the time necessary
for their expansion--and this high goal may be attained. Development
is all that is required, and not a change of quality. There need be
no absolute breach of continuity between us and our loftier brothers
yet to come.
We have guarded ourselves against saying that the inferring of thought
from material combinations and arrangements would be an inference _à
priori_. The inference meant would be the same in kind as that which
the observation of the effects of food and drink upon the mind would
enable us to make, differing only from the latter in the degree of
analytical insight which we suppose attained. Given the masses and
distances of the planets, we can infer the perturbations consequent on
their mutual attractions. Given the nature of a disturbance in water,
air, or aether--knowing the physical qualities of the medium we can
infer how its particles will be affected. In all this we deal with
physical laws. The mind runs with certainty along the line of thought
which connects the phenomena, and from beginning to end there is no
break in the chain. But when we endeavour to pass by a similar
process from the phenomena of physics to those of thought, we meet a
problem which transcends any conceivable expansion of the powers which
we now possess. We may think over the subject again and again, but it
eludes all intellectual presentation. We stand at length face to face
with the Incomprehensible. The territory of physics is wide, but it
has its limits from which we look with vacant gaze into the region
beyond. Let us follow matter to its utmost bounds, let us claim it in
all its forms--even in the muscles, blood, and brain of man
himself--as ours to experiment with and to speculate upon. Casting
the term "vital force" from our vocabulary, let us reduce, if we can,
the visible phenomena of life to mechanical attractions and
repulsions. Having thus exhausted physics, and reached its very rim, a
mighty Mystery still looms beyond us. We have, in fact, made no step
towards its solution. And thus it will ever loom, compelling the
philosophies of successive ages to confess that
"We are such stuff
As dreams are made of, and our little life
Is rounded by a sleep."
In my work on 'Heat,' published in 1863 and republished many times
since, I employ the precise language thus extracted from the 'Saturday
Review.'
The distinction is here clearly brought out which I had resolved at
all hazards to draw--that, namely, between what men knew or might
know, and what they could never hope to know. Impart simple
magnifying power to our present vision, and the atomic motions of the
brain itself might be brought into view. Compare these motions with
the corresponding states of consciousness, and an empirical nexus
might be established; but 'we try to soar in a vacuum when we
endeavour to pass by logical deduction from the one to the other.'
Among these brain-effects a new product appears which defies
mechanical treatment. We cannot deduce motion from consciousness or
consciousness from motion as we deduce one motion from another.
Nevertheless observation is open to us, and by it relations may be
established which are at least as valid as those of the deductive
reason. The difficulty may really lie in the attempt to convert a
datum into an inference--an ultimate fact into a product of logic. My
desire for the moment, however, is not to theorise, but to let facts
speak in reply to accusation.
The most 'materialistic' speculation for which I was responsible,
prior to the 'Belfast Address,' is embodied in the following extract
from a brief article written as far back as 1865: 'Supposing the
molecules of the human body, instead of replacing others, and thus
renewing a pre-existing form, to be gathered first-hand from nature,
and placed in the exact relative positions which they occupy in the
body. Supposing them to have the same forces and distribution of
forces, the same motions and distribution of motions--would this
organised concourse of molecules stand before us as a sentient,
thinking being? There seems no valid reason to assume that it would
not. Or supposing a planet carved from the sun, set spinning round an
axis, and sent revolving round the sun at a distance equal to that of
our earth, would one consequence of the refrigeration of the mass be
the development of organic forms? I lean to the affirmative.' This is
plain speaking, but it is without 'dogmatism.' An opinion is
expressed, a belief, a leaning--not an established 'doctrine.'
The burthen of my writings in this connection is as much a recognition
of the weakness of science as an assertion of its strength. In 1867,
I told the working men of Dundee that while making the largest demand
for freedom of investigation; while considering science to be alike
powerful as an instrument of intellectual culture, and as a ministrant
to the material wants of men; if asked whether science has solved, or
is likely in our day to solve, 'the problem of the universe,' I must
shake my head in doubt. I compare the mind of man to a musical
instrument with a certain range of notes, beyond which in both
directions exists infinite silence. The phenomena of matter and force
come within our intellectual range; but behind, and above, and around
us the real mystery of the universe lies unsolved, and, as far as we
are concerned, is incapable of solution.
While refreshing my mind on these old themes I appear to myself as a
person possessing one idea, which so over-masters him that he is never
weary of repeating it. That idea is the polar conception of the
grandeur and the littleness of man--the vastness of his range in some
respects and directions, and his powerlessness to take a single step
in others. In 1868, before the Mathematical and Physical Section of
the British Association, then assembled at Norwich, I repeat the same
well-worn note:
'In thus affirming the growth of the human body to be mechanical, and
thought as exercised by us to have its correlative in the physics of
the brain, the position of the "materialist," as far as that position
is tenable, is stated. I think the materialist will be able finally
to maintain this position against all attacks, but I do not think he
can pass beyond it. The problem of the connection of body and soul is
as insoluble in its modern form as it was in the pre-scientific ages.
Phosphorus is a constituent of the human brain, and a trenchant German
writer has exclaimed, "Ohne Phosphor kein Gedanke!" That may or may
not be the case; but, even if we knew it to be the case, the knowledge
would not lighten our darkness. On both sides of the zone here
assigned to the materialist, he is equally helpless. If you ask him
whence is this "matter" of which we have been discoursing--who or what
divided it into molecules, and impressed upon them this necessity of
running into organic forms--he has no answer. Science is also mute in
regard to such questions. But if the materialist is confounded and
science is rendered dumb, who else is prepared with an answer? Let us
lower our heads and acknowledge our ignorance, priest and philosopher,
one and all.'
*****
The roll of echoes which succeeded the Lecture delivered by Professor
Virchow at Munich on September 22, 1877, was long and loud. The
'Times' published a nearly full translation of the lecture, and it was
eagerly commented on in other journals. Glances from it to an Address
delivered by me before the Midland Institute in the autumn of 1877,
and published in this volume, were very frequent. Professor Virchow
was held up to me in some quarters as a model of philosophic caution,
who by his reasonableness reproved my rashness, and by his depth
reproved my shallowness. With true theologic courtesy I was
sedulously emptied, not only of the 'principles of scientific
thought,' but of 'common modesty' and 'common sense.' And though I am
indebted to Professor Clifford for recalling in the 'Nineteenth
Century' for April the public mind in this connection from heated
fancy to sober fact, I do not think a brief additional examination of
Virchow's views, and of my relation to them, will be out of place
here.
The key-note of his position is struck in the preface to the excellent
English translation of his lecture--a preface written expressly by
himself. 'Nothing,' he says, 'was farther from his intention than any
wish to disparage the great services rendered by Mr. Darwin to the
advancement of biological science, of which no one has expressed more
admiration than himself. On the other hand, it seemed high time to
him to enter an energetic protest against the attempts that are made
to proclaim the problems of research as actual facts, and the opinions
of scientists as established science.' On the ground, among others,
that it promotes the pernicious delusions of the Socialist, Virchow
considers the theory of evolution dangerous; but his fidelity to truth
is so great that he would brave the danger and teach the theory, if it
were only proved. 'However dangerous the state of things might be,
let the confederates be as mischievous as they might, still I do not
hesitate to say that from the moment when we had become convinced that
the evolution theory was a perfectly established doctrine--so certain
that we could pledge our oath to it, so sure that we could say, "Thus
it is"--from that moment we could not dare to feel any scruple about
introducing it into our actual life, so as not only to communicate it
to every educated man, but to impart it to every child, to make it the
foundation of our whole ideas of the world, of society, and the State,
and to base upon it our whole system of education. This I hold to be
a necessity.'
It would be interesting to know the persons designated by the pronoun
'we' in the first sentence of the foregoing quotation. No doubt
Professor Haeckel would accept this canon in all its fulness, and
found on it his justification. He would say without hesitation: 'I am
convinced that the theory of evolution is a perfectly established
doctrine, and hence on your own showing I am justified in urging its
introduction into our schools.' It is plain, however, that Professor
Virchow would not accept this retort as valid. His 'we' must cover
something more than Professor Haeckel. It would probably cover more
even than the audience he addressed; for he would hardly affirm, even
if every one of his hearers accepted the theory of evolution, that
that would be a sufficient warrant for forcing it upon the public at
large. His 'we,' I submit, needs definition. If he means that the
theory of evolution ought to be introduced into our schools, not when
experts are agreed as to its truth, but when the community is prepared
for its introduction, then, I think, he is right, and that, as a
matter of social policy, Dr. Haeckel would be wrong in seeking to
antedate the period of its introduction. In dealing with the
community great changes must have timeliness as well as truth upon
their side. But if the mouths of thinkers be stopped, the necessary
social preparation will be impossible; an unwholesome divorce will be
established between the expert and the public, and the slow and
natural process of leavening the social lump by discovery and
discussion will be displaced by something far less safe and salutary.
The burthen, however, of this celebrated lecture is a warning that a
marked distinction ought to be made between that which is
experimentally proved and that which is still in the region of
speculation. As to the latter, Virchow by no means imposes silence.
He is far too sagacious a man to commit himself, at the present time
of day, to any such absurdity. But he insists that it ought not to be
put on the same evidential level as the former. 'It ought,' as he
poetically expresses it, I to be written in small letters under the
text.' The audience ought to be warned that the speculative matter is
only _possible_, not _actual_ truth--that it belongs to the region of
'belief,' and not to that of demonstration. As long as a problem
continues in this speculative stage it would be mischievous, he
considers, to teach it in our schools. 'We ought not,' he urges, 'to
represent our conjecture as a certainty, nor our hypothesis as a
doctrine: this is inadmissible.' With regard to the connection between
physical processes and mental phenomena he says: 'I will, indeed,
willingly grant that we can find certain gradations, certain definite
points at which we trace a passage from mental processes to processes
purely physical, or of a physical character. Throughout this
discourse I am not asserting that it will never be possible to bring
psychical processes into an immediate connection with those that are
physical. All I say is that we have _at present_ no right to set up
this _possible_ connection as _a doctrine_ of science.' In the next
paragraph be reiterates his position with reference to the
introduction of such topics into school teaching. 'We must draw,' he
says, 'a strict distinction between what we wish to _teach_, and what we
wish to _search for_. The objects of our research are expressed as
problems (or hypotheses). _We need not keep them to ourselves; we are
ready to communicate them to all the world_, and say "There is the
problem; that is what we strive for." ... The investigation of such
problems, in which the whole nation may be interested, cannot be
restricted to any one. This is Freedom of Enquiry. But the problem
(or hypothesis) is not, without further debate, to be made _a
doctrine_.' He will not concede to Dr. Haeckel 'that it is a question
for the schoolmasters to decide, whether the Darwinian theory of man's
descent should be at once laid down as the basis of instruction, and
the protoplastic soul be assumed as the foundation of all ideas
concerning spiritual being.' The Professor concludes his lecture thus:
'With perfect truth did Bacon say of old "_Scientia est potentia_." But
he also defined that knowledge; and the knowledge he meant was not
speculative knowledge, not the knowledge of hypotheses, but it was
objective and actual knowledge. Gentlemen, I think we should be
abusing our power, we should be imperilling our power, unless in our
teaching we restrict ourselves to this perfectly safe and unassailable
domain. From this domain _we may make incursions into the field of
problems_, and I am sure that every venture of that kind will then find
all needful security and support.' I have emphasised by italics two
sentences in the foregoing series of quotations; the other italics are
the author's own.
Virchow's position could not be made clearer by any comments of mine
than he has here made it himself. That position is one of the highest
practical importance. Throughout our whole German Fatherland,' he
says, men are busied in renovating, extending, and developing the
system of education, and in inventing fixed forms in which to mould
it. On the threshold of coming events stands the Prussian law of
education. In all the German States larger schools are being built,
new educational establishments are set up, the universities are
extended, "higher" and "middle" schools are founded. Finally comes
the question, What is to be the chief substance of the teaching?' What
Virchow thinks it ought and ought not to be, is disclosed by the
foregoing quotations. There ought to be a clear distinction made
between science in the state of hypothesis, and science in the state
of fact. In school teaching the former ought to be excluded. And, as
he assumes it to be still in its hypothetical stage, the ban of
exclusion ought, he thinks, to fall upon the theory of evolution.
*****
I now freely offer myself for judgment before the tribunal whose law
is here laid down. First and foremost, then, I have never advocated
the introduction of the theory of evolution into our schools. I
should even be disposed to resist its introduction before its meaning
had been better understood and its utility more fully recognised than
it is now by the great body of the community. The theory ought, I
think, to bide its time until the free conflict of discovery,
argument, and opinion has won for it this recognition. A necessary
condition here, however, is that free discussion should not be
prevented, either by the ferocity of reviewers or the arm of the law;
otherwise, as I said before, the work of social preparation cannot go
on. On this count, then, I claim acquittal, being for the moment on
the side of Virchow.
Besides the duties of the chair, which I have been privileged to
occupy in London for more than a quarter of a century, and which never
involved a word on my part, pro or con, in reference to the theory of
evolution, I have had the honour of addressing audiences in Liverpool,
Belfast, and Birmingham; and in these addresses the theory of
evolution, and the connected doctrine of spontaneous generation, have
been more or less touched upon. Let us now examine whether in my
references I have departed from the views of Virchow or not.
In the Liverpool discourse, after speaking of the theory of evolution
when applied to the primitive condition of matter, as belonging to
'the dim twilight of conjecture,' and affirming that 'the certainty
of experimental enquiry is here shut out,' I sketch the nebular theory
as enunciated by Kant and Laplace, and afterwards proceed thus:
'Accepting some such view of the construction of our system _as
probable_, a desire immediately arises to connect the present life of
our planet with the past. We wish to know something of our remotest
ancestry. On its first detachment from the sun, life, as we
understand it, could not have been present on the earth. How, then,
did it come there? The thing to be encouraged here is a reverent
freedom--a freedom preceded by the hard discipline which checks
licentiousness in speculation--while the thing to be repressed, both
in science and out of it, is dogmatism. And here I am in the hands of
the meeting, willing to end but ready to go on. _I have no right to
intrude upon you unasked the unformed notions which are floating like
clouds, or gathering to more solid consistency in the modern
speculative mind_.'
I then notice more especially the basis of the theory. Those who hold
the doctrine of evolution _are by no means ignorant of the uncertainty
of their data, and they only yield to it a provisional assent_. They
regard the nebular hypothesis as probable; and, in the utter absence
of any proof of the illegality of the act, they prolong the method of
nature from the present into the past. Here the observed uniformity of
nature is their only guide. Having determined the elements of their
curve in a world of observation and experiment, they prolong that
curve into an antecedent world, and accept as probable the unbroken
sequence of development from the nebula to the present time.' Thus it
appears that, long antecedent to the publication of his advice, I did
exactly what Professor Virchow recommends, showing myself as careful
as he could be not to claim for a scientific doctrine a certainty
which did not belong to it.
I now pass on to the Belfast Address, and will cite at once from it
the passage which has given rise to the most violent animadversion.
'Believing as I do in the continuity of nature, I cannot stop abruptly
where our microscopes cease to be of use. At this point the vision of
the mind authoritatively supplements that of the eye. By an
intellectual necessity I cross the boundary of the experimental
evidence, and discern in that "matter" which we, in our ignorance of
its latent powers, and notwithstanding our professed reverence for its
Creator, have hitherto covered with opprobrium, the promise and
potency of all terrestrial life.' Without halting for a moment I go on
to do the precise thing which Professor Virchow declares to be
necessary. 'If you ask me,' I say, 'whether there exists the least
evidence to prove that any form of life can be developed out of matter
independently of antecedent life, my reply is that evidence considered
perfectly conclusive by many has been adduced, and that were we to
follow a common example, and accept testimony because it falls in with
our belief, we should eagerly close with the evidence referred to. But
there is in the true man of science a desire stronger than the wish to
have his beliefs upheld; namely, the desire to have them true. And
those to whom I refer as having studied this question, believing the
evidence offered in favour of "spontaneous generation" to be vitiated
by error, cannot accept it. They know full well that the chemist now
prepares from inorganic matter a vast array of substances, which were
some time ago regarded as the products solely of vitality. They are
intimately acquainted with the structural power of matter, as
evidenced in the phenomena of crystallisation. They can justify
scientifically their _belief_ in its potency, under the proper
conditions, to produce organisms. But, in reply to your question,
they will frankly admit their inability to point to any satisfactory
experimental proof that life can be developed, save from demonstrable
antecedent life.' [Footnote: Quoted by Clifford, 'Nineteenth Century,'
3, p. 726.]
Comparing the theory of evolution with other theories, I thus express
myself: 'The basis of the doctrine of evolution consists, not in an
experimental demonstration--for the subject is hardly accessible to
this mode of proof--but in its general harmony with scientific
thought. From contrast, moreover, it derives enormous relative
strength. On the one side we have a theory, which converts the Power
whose garment is seen in the visible universe into an Artificer,
fashioned after the human model, and acting by broken efforts, as man
is seen to act. On the other side we have the conception that all we
see around us and feel within us--the phenomena of physical nature as
well as those of the human mind--have their unsearchable roots in a
cosmical life, if I dare apply the term, an infinitesimal span of
which is offered to the investigation of man.' Among thinking people,
in my opinion, this last conception has a higher ethical value than
that of a personal artificer. Be that as it may, I make here no claim
for the theory of evolution which can reasonably be refused.