In the same month in which Newton wrote to Mr. Pepys, we find him in correspondence with Mr. Locke. Displeased with his opinions respecting innate ideas, he had rashly stated that they struck at the root of all morality, and that he regarded the author of such doctrines as a Hobbist. Upon reconsidering these opinions, he addressed the following remarkable letter to Locke, written three days after his letter to Mr. Pepys, and consequently during the illness under which he then laboured: —

"SIR, — Being of opinion that you endeavoured to embroil me with women, and by other means, I was so much affected with it, as that when one told me you were sickly and would not live, I answered, 'twere better if you were dead. I desire you to forgive me this uncharitableness; for I am now satisfied that what you have done is just, and I beg your pardon for my having hard thoughts of <149> you for it, and for representing that you struck at the root of morality, in a principle you laid in your book of ideas, and designed to pursue in another book, and that I took you for a Hobbist.[1] I beg your pardon also for saying or thinking that there was a design to sell me an office, or to embroil me. — I am your most humble and unfortunate servant,


"At the BULL, in Shoreditch, London, Sept. 16th, 1693."

To this letter, characterized by Mr. Dugald Stewart as ingenuous and infantine in its simplicity, Locke returned the following answer, which, as the same author justly remarks, "is written with the magnanimity of a philosopher, and with the good-humoured forbearance of a man of the world, breathing throughout so tender and unaffected a veneration for the good as well as great qualities of the excellent person to whom it is addressed, as demonstrates at once the conscious integrity of the writer, and the superiority of his mind to little passions."[2]


"OATES, Oct. 5th, 1693.

"SIR, — I have been, ever since I first knew you, so entirely and sincerely your friend, and thought you so much mine, that I could not have believed what you tell me of yourself, had I had it from anybody else. And, though I cannot but be mightily troubled that you should have had so many wrong and unjust thoughts of me, yet next to the return of good offices, such as from a sincere good will I have ever done you, I receive your acknowledgment of the contrary as the kindest thing you have done me, since it gives me hopes I have not lost a friend I so much valued. After what your letter expresses, I shall not need to say anything to justify myself to you. I shall always think your own reflection on my carriage, both to you and all mankind, will sufficiently do that. Instead of that, give me leave to assure you that I am more ready to forgive you than you can be to desire it; and I do it so freely and fully, that I wish for nothing more than the opportunity to convince you that I truly love and esteem you, and that I have the same good will for you as if nothing of this had happened. To confirm this to you more fully, I should be glad to meet you any where, and the rather, because the conclusion of your letter makes me apprehend it would not be wholly useless to you. But whether you think it fit or not, I leave wholly to you. I shall always be ready to serve you to my utmost, in any way you shall like, and shall only need your commands or permission to do it.

"My book is going to press for a second edition; and, though I can answer for the design with which I write it, yet, since you have so opportunely given me notice of what you have said of it, I should take it as a favour if you would point out to me the places that gave occasion <151> to that censure, that, by explaining myself better, I may avoid being mistaken by others, or unawares doing the least prejudice to truth or virtue. I am sure you are so much a friend to them both, that, were you none to me, I could expect this from you. But I cannot doubt but you would do a great deal more than this for my sake, who, after all, have all the concern of a friend for you, wish you extremely well, and am, without compliment, &c."[3]

To this letter Newton made the following reply: —

"SIR, — The last winter, by sleeping too often by my fire, I got an ill habit of sleeping; and a distemper, which this summer has been epidemical, put me farther out of order, so that when I wrote to you, I had not slept an hour a night for a fortnight together, and for five days together not a wink. I remember I wrote to you, but what I said of your book I remember not. If you please to send me a transcript of that passage, I will give you an account of it if I can. — I am your most humble servant,


"CAMBRIDGE, Oct. 15th, 1693."

Although the first of these letters evinces the existence of a nervous irritability which could not fail to arise from want of appetite and of rest, yet it is obvious that its author was in the full possession of his mental powers. The answer of Mr. Locke, indeed, is written upon the supposition that Newton was then qualified to point out the objectionable passages in his Book, that they might be corrected and better explained; and it deserves to be <152> remarked, that Mr. Dugald Stewart, who first published a portion of these letters, never imagined that Newton was labouring under any mental alienation.

In the autumn of 1693, when Newton was suffering most severely from want of appetite and sleep, we find him deeply engaged in biblical research — collating ancient manuscripts of the New Testament — criticising the manuscript works of Dr. John Mill of Edmund Hall, Oxford, and communicating to him the results of his labours. Only two letters of this correspondence have been found, the letter from Dr. Mill to Newton, requesting the return of his manuscript with his observations, and Newton's reply, showing how busily he had been occupied in the task assigned to him by his friend.[4]

Among the other evidences of Newton's consistency of mind, in May 1694, when he is said to have been only beginning to understand the Principia, we may mention the visit paid to him in the beginning of that month by David Gregory, who went to Cambridge for the purpose of "consulting the divine author of the Principia," on certain errors which appeared to have crept into that work.[5] On the 7th of the same month, probably when Gregory was at Cambridge, we find Newton denouncing the imposture of the haunted house, and scolding the Fellows <153> of Trinity and several of the scholars for their credulity.[6]


The system of Hobbes was at this time very prevalent. According to Dr. Bentley, "the taverns and coffee-houses, nay, Westminster Hall, and the very churches, were full of it;" and he was convinced, from personal observation, that "not one English infidel in a hundred was other than a Hobbist."— Monk's Life of Bentley, p. 31.


Newton and Locke occasionally corresponded on theological subjects. In the autumn of 1702, Newton visited Locke at Oates, and having read his Essay on the Corinthians, he promised to give him his observations and opinion upon it after a more careful perusal. Locke accordingly sent it to him before Christmas 1702; but in consequence of receiving no answer, he wrote to him again on the 30th April 1703, and received his observations in a letter dated May 15, 1703, published by Lord King. In this letter Newton tells him that he had purposed to pay him a visit at Oates, on his way to Cambridge, in summer, but was "now uncertain of this journey." We believe they never met again. Locke died on the 28th October 1704, in the seventy-third year of his age; and it has been stated that Newton visited his tomb at High Laver, in Essex, in all probability when he paid his next visit to Cambridge.


"The draft of this letter is indorsed J. L. to I. Newton." I have not found the original among Newton's papers.


The letter of Dr. Mill, dated Nov. 7, 1693, I found among Newton's papers. That of Newton, dated Jan. 29, 16934, is preserved in the library of Queen's College, Oxford, and is No. 26 of the printed Catalogue. Having been kindly favoured with a copy of this letter by Dr. Fox, I have given both of them in the APPENDIX, No. XII., as they possess a peculiar interest.


"Quoniam varii errores in propositiones 37 et 38 (Lib. 2) irrepsisse, illos omnes restitutos hic apponam, prout in auctoris exemplari inveni, ineunte Maio 1694, dum Cantabrigiæ hærerem, consulendi divini auctoris gratia." — MS. of David Gregory, Rigaud, Hist. Essay/>, p. 100. Mr. Rigaud adds, that this is "the place in which Fatio says he convinced Newton of his mistakes." See Edinburgh Transactions, 1829, vol. xii. p. 71.


The following account of this affair is given by Mr. Edleston from De la Pryme's Diary: — "On {the} Monday {night} likewise, there being a great number of people at the door {of the haunted house, — it was a house opposite St. John's College, in the occupation of Valentine Austin,} there chanced to come by Mr. Newton, Fellow of Trinity College, a very learned man, and perceiving our Fellows to have gone in {three Fellows of St. John's, with a Fellow Commoner of that College, had rushed in armed with pistols,} and seeing several scholars about the door, 'Oh ye fools!' says he, 'will ye never have any wit? know ye not that all such things are mere cheats and impostures? fie, fie! go home for shame,' and so he left them, scorning to go in." In this Diary, to which we have already referred, there is a full account of the proceedings of the "spirit," which the writer of the Diary had received in a letter from Cambridge. — Edleston's Correspondence, &c., p. lxiv.

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Professor Rob Iliffe
Director, AHRC Newton Papers Project

Scott Mandelbrote,
Fellow & Perne librarian, Peterhouse, Cambridge

Faculty of History, George Street, Oxford, OX1 2RL -

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