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. FOOTNOTES: [1] Robert, the second son, died in childhood. [2] Dr. Brydon resided on a small but beautiful property overlooking the Cromarty Firth, and, after his death, Dr. Romanes rented the place from its owners, who were distant cousins of Mrs. Romanes, in order that 'George might have some shooting.' [3] His younger sister records an odd experience of hers. At the time of her brother's accident she was travelling in Spain with her father and sister, and one day was taken suddenly ill, became slightly delirious, and expressed great anxiety on George's account. Afterwards, on comparing notes, it was found that the time of his accident coincided with that of her illness. [4] Mr. Cautley writes: 'I have never seen Romanes, under the greatest provocation, out of temper. Always gentle, always kind, never overbearing ... never forgetful of friends.' [5] Prof. E. R. Lankester in _Nature_, May 1894. [6] But he also communicated a paper to the Royal Society entitled, 'The Influence of Injury on the Excitability of Motor Nerves.' Of this paper Professor Burdon Sanderson says that the observations were made with great care, and that the new facts recorded have been fully confirmed by later observers. This work was done at Cambridge.