Feb. 15, 1883 | 
NATURE 
363 
article of mine which appeared in the Covlemporary Review. 
As he appears to solicit a further statement of my views, I shall 
supply a brief explanation of those passages in my article to 
which he refers. 
This article, I must begin by observing, was written in reply 
to a criticism on my essay in the ‘‘ NATURE Series” (‘‘ Scien- 
tific Evidences of Organic Evolution”), and, being intentionally 
limited to the ground covered by that criticism, it did not require 
to discuss all the points raised by Prof. Gray. But without 
reference to the original article, I shall now consider these points 
seriatim. 
First, I am requested to state what I mean by urging that inmy 
opinion there is no logical point of contact betw een natural science 
and natural theology. My answer is that natural science, as 
such, can only be legitimately concerned with the investigation 
of natural or physical causes, and that in whatever degree it 
presumes to pass beyond the territory of such investigation, it 
ceases to be natural science, and becomes ontological specula- 
tion. In other words, there is no point of logical contact 
between the methods and aims of natural science, as such, and 
the super-scientific conclusions which constitute the aim of natu- 
ral theology. For it is the aim of natural theology to establish 
certain very definite conclusions with reference to the existence 
and the character of a ‘‘causa causarum,” which is acknow- 
ledged to be supernatural at least to the extent of being in- 
scrutable by any of the methods possible to science. But from 
this sufficiently obvious position it does not follow, as my critic 
seems to insist, ‘‘that because natural phenomena can be re- 
duced to-laws and sequences of cause and effect, no legitimate 
or rational inference can be made by the human mind to a causa 
causarum.” Whether or not any such legitimate or rational 
inference can be made, from the data mentioned, dy the human 
mind is not here the question, and therefore I decline to enter 
uponit. The only question before us is as to whether any such 
inference can be drawn by the human mind from the province 
of natural science, and I say that this question must be answered 
in the negative, seeing that there is, as I have just explained, an 
absence of logical contact between the sphere of natural science 
and the sphere of supernatural theology. Any inferences of the 
kind in question, be they legitimate or not, are drawn from the 
general order of Nature—?.e. feom the wmiversal prevalence of 
““laws and sequences of cause and effect’’; therefore they are 
not really or logically strengthened by a mere enumeration of 
particular instances of such laws and sequences all similar in 
kind. The so-called law of causation as a whole being known, 
and its universality recognised, its true argumentative value to 
the theory of theism is not influenced by the explicit formula- 
tion of any number of its specific cases which the progress of 
science has been able, or may be able, to supply. 
I allow, of course, that the human mind cannot avoid occu- 
pying itself with the most momentous of all questions—the 
nature of the First Cause and of its relations to the universe— 
or, in the words of Prof. Gray, that ‘‘such questions are in- 
evitable” ; I am only concerned with explaining why I conceive 
that such questions are not affected by any of the methods or 
results of natural science, which do not stand in any logical 
relation to them. And this introduces me to the next point in 
Prof. Gray’s criticism. He says that I am inconsistent in first 
alleging that there is no point of logical contact between natural 
science and natural theology, and then proceeding to affirm that 
the theory of natural selection has proved destructive of the 
evidence of special design in organic nature. But I think this 
charge must have been made without due reflection ; for, if a 
man believes that there is no logical connection between one 
thing and another, I do not understand why he should be deemed 
inconsistent merely because he endeavours to show the fictitious 
character of the logical connection which has been erroneously 
supposed to exist. Assuredly I think that ‘‘ Darwin’s theory need 
not, and legitimately should not, concern itself with natural 
theology”; but I also think that natural theology should not 
seek to obtain unreal support from natural science, and it is be- 
cause natural theology has sought to do this in one conspicuous 
instance, and in that one instance has been as conspicuously met 
by Darwin’s theory, that, as I explained in my article, it seemed 
to me desirable, both in the interests of science and of theology, 
henceforth clearly to recognise the logical gulf which is fixed 
between these two departments of human thought. 
Next Prof. Gray observes, and quite correctly, that my view 
of the matter as a whole is fairly presented by the followi g sen- 
tences, which he quotes :— 
“The facts of organic nature furnish no evidence of design of 
a quality other or better than any of the facts of inorganic 
nature.”’ ‘* Or, otherwise stated, there is nothing in the theory 
of natural selection incompatible with the theory of theism; but 
neither does the former theory supply evidence of the latter. Now 
this is just what the older theory of special creation did ; for it 
would be proof positive of intelligent design if it could be shown 
that all species of plants and animals were created, that is, sud- 
denly introduced into the complex conditions of their life ; for it 
is quite inconceivable that any cause other than intelligence 
could be competent to adapt an organism to its environment 
suddenly,” 
Prof. Gray then asks: ‘‘Is the writer of this quite sure that 
any cause other than intelligence could be competent to adapt 
existing organisms to their environment gvadually 2?” My answer 
is but too easy. I must leave to others the happy position of 
being ‘‘ quite sure” about anything relating to the possibilities 
of supernatural causation. or aught that I know, or for aught 
that any living man can ever know, not only all existing 
organisivs, but all existing atoms, may have depended from all 
tme, and for all their changes, sudden or gradual, upon ‘‘ intel- 
ligence,’’ without which they may not have been able either to 
have lived or to have moved, or even to have had their being. 
But bow does this necessary ignorance on my part affect my 
statement that “the facts of organic nature present no evidence 
of design of a quality other or better than any of the facts of 
Inorganic nature”? I confess I do not see how this failure in 
the evidence of design is made good by telling me that, for any- 
thing to the contrary of which 1 can be ‘‘quite:ure,”’ there may 
have been a designer. For I cannot follow my critic where he 
argues that the element of a supposed sudden introduction cf an 
organism to its environment makes no difference in the evidence 
of its adaptations to its environment having been designed. He 
asks : ‘‘ How is this presumption [¢.e. that of special design] 
negatived or impaired by the supposition of Darwin’s theory, 
that the ancestors were not always like the offspring, but dif- 
fered from time to time in small particulars, yet so as always to 
be in compatible relations with their environment?” The 
answer is, that if we suppose the sudden or special creation of 
organisms in manifold adaptation to their several environments, 
we can conceive of no cause other than intelligence as com- 
petent to produce the adaptations, whereas, if the adaptations 
have been effected gradually, and dy the successive climination of 
the more favourable variations by a process of natural causation, 
we clearly have a totally different case to contemplate, and one 
which is destitute of any evidence of special design. Assuredly 
** cradualness is in nowise incompatible with design,” and I do 
not suppose that there has ever been any one so foolish as to 
imagine that it is; but all the same, the progressive adaptations 
of structures to functions by such a purely physical cause as 
natural selection when once clearly revealed must destroy all 
special or particular evzdence of design, even supposing such 
design to exist. For under this point of view it was on/y those 
variations which were ‘‘in compatible relations with the environ- 
ment” which were able to survive. Only if it could be shown 
that the variations always took place exclusively in the directions 
required for a development of the adaptations, so as to leave no 
room for the operation of the physical cause in question—only 
then would the evidence of design as deduced from the theory of 
evolution be comparable with that evidence as deduced from the 
theory of special creation. 
Towards the close of his letter, Prof. Gray seems to have 
anticipated this obvious rejoinder, for he says that, in order to 
make the purely physical explanation tenable, ‘‘it must be 
shown that natural selection scientifically accounts for the adap- 
tation,” —z.e. as 1 understand, it must be shown that there is not 
some influence of an intelligent kind guiding the occurrence of 
the variations in the requisite lines, which, having been thus 
intelligently caused to arise, are then seized upon by natural 
selection. If this is Prof. Gray’s meaning, he is certainly 
wrong in attributing it to Mr. Darwin, and I cannot see that it 
is a meaning of any argumentative use. For the burden of proof 
lies with the natural theologian to show that there Aas been 
some such intelligent guidance of the variations, not with the 
evolutionist to show cause why there may not haye been such 
guidance. The evolutionist may freely admit that natural selec- 
tion has probably not been the only physical cause at work, and 
even that the variations supplied to natural selection may not 
have been wholly fortuitous, but may sometimes have occurred 
along favourable lines as ‘‘responses of the organisms to their 
