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Darwin Correspondence Project

From G. J. Romanes   8 December 1878

18 Cornwall Terrace, Regent’s Park:

Sunday, Dec. 1878.

My dear Mr. Darwin,—

Many thanks for your portrait—not only from myself but also from the ‘future Mrs. Romanes.’

I am glad that you think well of the literary style of the book on Theism. As regards the remarks of the supposed theologian, I have no doubt that he is entitled to them. The only question is whether I have been successful in making out that all natural cases must reasonably be supposed to follow from the conservation of energy. If so, as the transmutations of energy from heat to electricity &c. all take place in accordance with law, and as the phenomena of polarity in crystals &c. do the same, it follows that neither these nor any other class of phenomena afford any better evidence of Deity than do any other class of phenomena. Therefore, if all laws follow from the persistence of force, the question of Deity or no Deity would simply become the question as to whether force requires to be created or is self-existent. And if we say it is created, the fact of self-existence still requires to be met in the Creator.

Of course it may be denied that all laws do follow from the persistence of force. And this is what I mean by the distinction between a scientific and a logical proof. For in the last resort all scientific proof goes upon the assumption that energy is permanent, so that if from this assumption all natural laws and processes admit of being deduced, it follows that for a scientific cosmology no further assumption is required; all the phenomena of Nature receive their last or ultimate scientific explanation in this the most ultimate of scientific hypotheses. But now logic may come in and say, ‘This hypothesis of the persistence of force is no doubt verified and found constantly true within the range of science (i.e. experience), so that thus far it is not only an hypothesis but a fact. But before logic can consent to allow this ultimate fact of science to be made the ultimate basis of all cosmology, I must be shown that it is ultimate, not merely in relation to human modes of research, but also in a sense absolute to all else.’

But the more I think about the whole thing the more am I convinced that you put it into a nutshell when you were here, and that there is about as much use in trying to illuminate the subject with the light of intellect as there would be in trying to illuminate the midnight sky with a candle. I intend, therefore, to drop it, and to take the advice of the poet, ‘Believe it not, regret it not, but wait it out, O Man.’

G. J. R.

I return the papers, having taken down the references. The books I shall return when read, but honey-mooning may prolong the time.


Thinks conservation of energy not evidence for Deity. Agrees with CD that there is little hope to illuminate subject with light of intellect. Intends to drop it.

Letter details

Letter no.
Romanes, G. J.
Darwin, C. R.
Sent from
London, Cornwall Terrace, 18
Source of text
Romanes (1896): 86

Please cite as

Darwin Correspondence Project, “Letter no. 11779,” accessed on 16 January 2017,