Exclusive: John von Neumann’s letters to Norbert Wiener on computational machinery (1945)

For a special treat to all my readers I am putting these previously difficult to access letters online for the first time.

In this exchange I’ve selected two from Dr. von Neumann that I found to be especially interesting, and which I was able to secure special permission to reproduce from the copyright holder and the American Mathematical Society.

Please make the appropriate credits if you wish to further copy.

Letter 1 “

Professor Norbert Wiener
November 20, 1945
Mathematics Department
Massachusetts Institute of Technology
Cambridge 39, Massachusetts

Dear Norbert:

The negotiations at Princeton have come to a conclusion, with the result that the Institute of Advanced Study and the Radio Corporation of America (whose research laboratory is, as you know, in Princeton), with the cooperation of Princeton University, have decided to undertake a joint high-speed, automatic, electronic computer development. While this is to be a community effort, it is agreed between all parties that the completed computer is to be located at the Institute, and used exclusively as a research tool. I have been offered the over-all direction of this

As far as I can see, the project is adequately financed and has the necessary guarantees of manpower, availability of the RCA’s experience in various pertinent fields, etc.

Since I have always urged such an enterprize on the Institute for Advanced Study authorities, and insisted that it is of great importance in several vital respects, I feel that it is now my prime responsibility to see it through here.

I need not tell you how much I regret that this means that I cannot join you at Tech (MIT), especially since I am sure that without the decisive encouragement that I received from you and from the Tech authorities I would have hardly had the perseverance and the strength of conviction which are the minimum requirements in this project. On the other hand, I hope that we shall work together in the field just the same. I think that we should discuss the modalities as quickly as possible.

I am staying in Princeton continuously until November 30. Then I am going
for 2.5 – 3 weeks to Los Alamos. This trip, plus the Christmas vacation eliminate the month of December. Could you find the time to visit here before the end of this month, say between November 26 (Monday) and 29 (Thursday), both inclusive? I hope that you can do this and will accept our invitation to come as a guest of the Institute.

Hoping to see you soon, and very much looking forward to it,

Yours as ever,

J. von Neumann

Letter 2 “

November 29, 1946

Dear Norbert:

This letter represents an effort to do better than I estimated in my letter of November 25, in which I proposed that we might get together for the afternoon or evening of December 4 in Cambridge, and indicated only somewhat vaguely what the subject was that I would like to discuss with you. I am now trying to give you a more detailed advance notice, hoping that this will make our discussion on December 4 more specific.

Our thoughts – I mean yours and Pitts’ and mine- were so far mainly focused on the subject of neurology, and more specifically on the human nervous system and there primarily on the central nervous system. Thus, in trying to understand the function of automata and the general principles governing them, we selected for prompt action the most complicated object under the sun – literally. In spite of its formidable complexity this subject has yielded very interesting information under the pressure of the efforts of Pitts and McCulloch, Pitts, Wiener and Rosenblueth. Our thinking – or at any rate mine – on the entire subject of automata would be much more muddled than it is, if these extremely bold efforts – with which I would like to put on one par the very un-neurological thesis of R. Turing – had not been made. Yet, I think that these successes should not blind us to the difficulties of the subject, difficulties, which, I think, stand out now just as – if not more-forbiddingly as ever.

The difficulties are almost too obvious to mention: They reside in the exceptional complexity of the human nervous system, and indeed of any nervous system. What seems worth emphasizing to me is, however, that after the great positive contribution of Turing – cum – Pitts – and-MeCulloch is assimilated, the situation is rather worse than better than before. Indeed, these authors have demonstrated in absolute and hopeless generality, that anything and everything Brouwerian can
be done by an appropriate mechanism, and specifically by a neural mechanism and that even one, definite mechanism can be “universal”. Inverting the argument: Nothing that we may know or learn about the functioning of the organism can give, without “microscopic’, cytological work any clues regarding the further details of the neural mechanism. I know that this was well known to Pitts, that the ‘nothing’ is not wholly fair, and that it should be taken with an appropriate dose of salt, but I think that you will feel with me the type of frustration that I am trying to ress
(H. N. Russell used to say, or to quote, that if the astrophysicist found a general theory uniformly corroborated, his exclamation should be “Foiled again” Since no experimenta crucis would emerge.) After these devastatingly general and positive results one is therefore thrown back on microwork and cytology – where one might have remained in the first place. (This “remaining there” is, of course, highly figurative in my case, who have never been there.) Yet, when we are in that held the complexity of the subject is overawing. To understand the brain with neurological
methods seems to me about as hopeful as to want to understand the ENIAC with no instrument at one’s disposal that is smaller than about 2 feet across its critical organs, with no methods of intervention more delicate than playing with a fire hose (although one might ill it with kerosene or nitroglycerine instead of water) or dropping cobblestones into the circuit. Besides the system is not even purely digital (i.e. neural): It is intimately connected to a very complex analogy (i.e. humoral or hormnonal) system, and, almost every feedback loop goes through both sectors, if not through the “outside world (i.e. the world outside the epidermis or within the digestive system) as well. And it contains, even in its digital part, a million times more units than the ENIAC. And our intellectual possibilities relatively to it are about as good as some bodies vis-a-vis the ENIAC, if he has never heard of any part of arithmetic. It is true that we know a little about the syndromes of a few selected breakdowns – but that is not much.

My description is intentionally exaggerated and belittling, but don’t you think that there is an element of truth in it?

Next: If we go to lower organisms from man with 10^10 neurons to ants with 10^6 or to some sub-animal with, say, 10^2 neurons – we lose nearly as much as we gain. As the digital (neural) part simplifies, the analogy (humoral) part gets less accessible, the typical malfunctions less known, the subject less articulate, and our possibilities of communicating with it poorer and poorer in content.

Further: I doubt that the “Gestalt” theory, or anybodies verbal theory will help any. The central nervous system is complicated, and therefore its attributes and characteristics have every right to be complicated. Let not our facile familiarity with it, through the medium of the subjective consciousness, fool us into illusions in this respect.

What are we then to do? I would not have indulged in such a negative tirade if I did not believe that I see an alternative. In fact, I have felt all these doubts for the better part of a year now, and I did not talk about them because I had no idea as to what one might say in a positive direction.

I think now that there is something positive to be said, and I would like to indicate in which direction I see it.

I feel that we have to turn to simpler systems. It is a fallacy, if one argues, that because the neuron is a cell (indeed part of its individual insulating wrapping is multicellular), we must consider multicellular organisms only. The cell is clearly an excellent “standard component”, highly flexible and suited to diferentiation in form and in function, and the higher organisms use it freely. But its self-reproductivity indicates that it has in itself some of the decisive attributes of the integrated organisms- and some cells (e.g. the leukocytes) are self-contained, complete beings. This in itself should make one suspicious in selecting the cells as the basic “undefined” concepts of an axiomatism. To be more par terre: Consider, in any field of technology, the state of affairs which is characterized by the development of highly complex “standard components”, which are at the same time individualized, well sited to mass production, and (in spite of their “standard” character) well suited to purposive differentiation. This is clearly a late, highly developed style, and not the ideal one for a first approach of an outsider to the subject, for an effort towards understanding. For the purpose of understanding the subject, it is much better to study an earlier phase of its evolution, preceding the development of this high standardization – with differentiation. I.e. to study a phase in which these “elegant components do not yet appear. This is especially true, if there is reason to suspect already in that archaic stage mechanisms (or organisms) which exhibit the most specific traits of the simplest representatives of the above mentioned “late” stage.

Now the less-than-cellular organisms of the virus or bacteriophage type do possess the decisive traits of any living organism: They are self-reproductive and they are able to orient themselves in an unorganized milieu, to move towards food, to appropriate it, and to use it. Consequently a “true” understanding of these organisms may be the first relevant step forward and possibly the greatest step that may at all be required.

I would, however, put on “true” understanding the most stringent interpretation possible: That is, understanding the organism in the exacting sense in which one may want to understand a detailed drawing of a machine – i.e. finding out where every individual nut and bolt is located, etc.

It seems to me that this is not at all hopeless. A typical bacteriophage, which can be multiplied at will (and hence “counted” – by the colonies it forms on a suitable substrate- as reliably as elementary particles can be “counted” by a Geiger-counter) is a phage that is parasitic, I think, on the Bacillus Coli. It has been extensively worked with, e.g. by Delbrueck at Vanderbilt. It is definitely an animal, with something like a head and a tail. Its dimensions are I think, ca. 60 microns. 25 microns x 25 microns, i.e. its volume is 60 x 25 x 25 x 10^-21 cm^3 = 3.7 x 10^-17 cm^3.
The density may be taken to be 1, hence its mass is about 3.7 x 10 grams. i.e. the same as about 2.5 x 10^7 H atoms. Since the average chemical composition of these things is usually about one C or N or O per one or two H, the average atomic weight of its constituents is about 6. Hence the number of atoms in it is about 4 x 10^6. Furthermore, it is known from the behavior of physiological membranes, that they are monomolecular – or oligomolecular – Langmuir-layers, which exercise their function in a highly mechanical way. E.g. the so-called “active permeability”: The peculiar ability to “permit” ions to pass through the membrane against an electrical field – an activity which clearly must, and demonstrably does, require an energy supply from the metabolism – and which is therefore better described as “pushing the ions across” than as “permitting them to pass”. I understand that here an ion simply gets seized by the opposite-polarity end of one of the rare (charged) radicals in the membrane, which then turns around and deposits the ion on the other side of the membrane. Very similar things can be said about the functioning of the “phosphate bond”, which seems to be the main physiological device for localized, short time energy storage – i.e. the equivalent of a spring. Thus one can really talk of “mechanical elements”, each of which may comprise 10 atoms or more. Thus the organism in question consists of six million atoms, but probably only of a few hundred thousand “mechanical elements”. I suppose (without having done it) that if one counted rigorously the number of “elements” in a locomotive, one might also wind up in the high ten thousands. Consequently this is a degree of complexity which is not necessarily beyond human endurance.

The question remains: Even if the complexity of the organisms of molecular weight 10^10 is not too much for us, do we have the observational means to ascertain all the facts? Or to be more lenient: If we do not possess such means now, can we at least conceive them, and could they be acquired by developments …

Letter 2 will be continued in my next post.

Samuel Johnson’s fascinating epistolary writing, ‘The Rambler No. 42’

Note that this is likely a fictional letter written by himself instead of an actual reader, from https://www.johnsonessays.com/the-rambler/misery-modish-solitude/

Originally published August 11, 1750, revised in 1756

A later editor added the title ‘The misery of a modish lady in solitude’

Mihi tarda fluunt ingrataque tempora.

Horace. liber primus I. Epistle 1. 15.

How heavily my time revolves along.




I am no great admirer of grave writings, and therefore very frequently lay your papers aside before I have read them through; yet I cannot but confess that, by slow degrees, you have raised my opinion of your understanding, and that, though I believe it will be long before I can be prevailed upon to regard you with much kindness, you have, however, more of my esteem than those whom I sometimes make happy with opportunities to fill my tea-pot, or pick up my fan. I shall therefore chuse you for the confidant of my distresses, and ask your counsel with regard to the means of conquering or escaping them, though I never expect from you any of that softness and pliancy, which constitutes the perfection of a companion for the ladies: as, in the place where I now am, I have recourse to the mastiff for protection, though I have no intention of making him a lap-dog.

My mamma is a very fine lady, who has more numerous and more frequent assemblies at her house than any other person in the same quarter of the town. I was bred from my earliest infancy in a perpetual tumult of pleasure, and remember to have heard of little else than messages, visits, playhouses, and balls; of the awkwardness of one woman, and the coquetry of another; the charming convenience of some rising fashion, the difficulty of playing a new game, the incidents of a masquerade, and the dresses of a court-night. I knew before I was ten years old all the rules of paying and receiving visits, and to how much civility every one of my acquaintance was entitled; and was able to return, with the proper degree of reserve or of vivacity, the stated and established answer to every compliment; so that I was very soon celebrated as a wit and a beauty, and had heard before I was thirteen all that is ever said to a young lady. My mother was generous to so uncommon a degree as to be pleased with my advance into life, and allowed me, without envy or reproof, to enjoy the same happiness with herself; though most women about her own age were very angry to see young girls so forward, and many fine gentlemen told her how cruel it was to throw new chains upon mankind, and to tyrannize over them at the same time with her own charms, and those of her daughter.

I have now lived two-and-twenty years, and have passed of each year nine months in town, and three at Richmond; so that my time has been spent uniformly in the same company, and the same amusements, except as fashion has introduced new diversions, or the revolutions of the gay world have afforded new successions of wits and beaux. However, my mother is so good an economist of pleasure, that I have no spare hours upon my hands; for every morning brings some new appointment, and every night is hurried away by the necessity of making our appearance at different places, and of being with one lady at the opera, and with another at the card-table.

When the time came of settling our schemes of felicity for the summer, it was determined that I should pay a visit to a rich aunt in a remote county. As you know the chief conversation of all tea-tables, in the spring, arises from a communication of the manner in which time is to be passed till winter, it was a great relief to the barrenness of our topicks, to relate the pleasures that were in store for me, to describe my uncle’s seat, with the park and gardens, the charming walks and beautiful waterfalls; and every one told me how much she envied me, and what satisfaction she had once enjoyed in a situation of the same kind.

As we are all credulous in our own favour, and willing to imagine some latent satisfaction in any thing which we have not experienced, I will confess to you, without restraint, that I had suffered my head to be filled with expectations of some nameless pleasure in a rural life, and that I hoped for the happy hour that should set me free from noise, and flutter, and ceremony, dismiss me to the peaceful shade, and lull me in content and tranquillity. To solace myself under the misery of delay, I sometimes heard a studious lady of my acquaintance read pastorals, I was delighted with scarce any talk but of leaving the town, and never went to bed without dreaming of groves, and meadows, and frisking lambs.

At length I had all my clothes in a trunk, and saw the coach at the door; I sprung in with ecstasy, quarrelled with my maid for being too long in taking leave of the other servants, and rejoiced as the ground grew less which lay between me and the completion of my wishes. A few days brought me to a large old house, encompassed on three sides with woody hills, and looking from the front on a gentle river, the sight of which renewed all my expectations of pleasure, and gave me some regret for having lived so long without the enjoyment which these delightful scenes were now to afford me. My aunt came out to receive me, but in a dress so far removed from the present fashion, that I could scarcely look upon her without laughter, which would have been no kind requital for the trouble which she had taken to make herself fine against my arrival. The night and the next morning were driven along with inquiries about our family; my aunt then explained our pedigree, and told me stories of my great grandfather’s bravery in the civil wars, nor was it less than three days before I could persuade her to leave me to myself.

At last economy prevailed; she went in the usual manner about her own affairs, and I was at liberty to range in the wilderness, and sit by the cascade. The novelty of the objects about me pleased me for a while, but after a few days they were new no longer, and I soon began to perceive that the country was not my element; that shades, and flowers, and lawns, and waters, had very soon exhausted all their power of pleasing, and that I had not in myself any fund of satisfaction, with which I could supply the loss of my customary amusements.

I unhappily told my aunt, in the first warmth of our embraces, that I had leave to stay with her ten weeks. Six only yet are gone, and how shall I live through the remaining four? I go out and return; I pluck a flower, and throw it away; I catch an insect, and when I have examined its colours set it at liberty; I fling a pebble into the water, and see one circle spread after another. When it chances to rain, I walk in the great hall, and watch the minute-hand upon the dial, or play with a litter of kittens, which the cat happens to have brought in a lucky time.

My aunt is afraid I shall grow melancholy, and therefore encourages the neighbouring gentry to visit us. They came at first with great eagerness to see the fine lady from London; but when we met, we had no common topick on which we could converse; they had no curiosity after plays, operas, or musick: and I find as little satisfaction from their accounts of the quarrels or alliances of families, whose names, when once I can escape, I shall never hear. The women have now seen me, know how my gown is made, and are satisfied; the men are generally afraid of me, and say little, because they think themselves not at liberty to talk rudely.

Thus I am condemned to solitude; the day moves slowly forward, and I see the dawn with uneasiness, because I consider that night is at a great distance. I have tried to sleep by a brook, but find its murmurs ineffectual; so that I am forced to be awake at least twelve hours, without visits, without cards, without laughter, and without flattery. I walk because I am disgusted with sitting still, and sit down because I am weary with walking. I have no motive to action, nor any object of love, or hate, or fear, or inclination. I cannot dress with spirit, for I have neither rival nor admirer. I cannot dance without a partner; nor be kind or cruel, without a lover.

Such is the life of Euphelia; and such it is likely to continue for a month to come. I have not yet declared against existence, nor called upon the destinies to cut my thread; but I have sincerely resolved not to condemn myself to such another summer, nor too hastily to flatter myself with happiness. Yet I have heard, Mr. Rambler, of those who never thought themselves so much at ease as in solitude, and cannot but suspect it to be some way or other my own fault, that, without great pain, either of mind or body, I am thus weary of myself: that the current of youth stagnates, and that I am languishing in a dead calm, for want of some external impulse. I shall therefore think you a benefactor to our sex, if you will teach me the art of living alone; for I am confident that a thousand and a thousand ladies, who affect to talk with ecstasies of the pleasures of the country, are in reality, like me, longing for the winter, and wishing to be delivered from themselves by company and diversion.

I am, Sir, Yours,


Due to the changing fashions over time even the greatest writers certainly no longer write like this anymore!

If you are likewise fascinated after reading I would highly recommend reading his other essays, freely accessible online. Note that it’s likely most, if not all, his ‘reader letters’ were actually fictional letters.

Nonetheless still impressive 270 years later.

A further analysis of Johnson’s epistles can be found here, JSTOR Arts & Sciences VII, paywalled.

Arthur C. Clarke proposing the idea of geostationary satellites, global peer to peer communication, and the GPS system in 1956

A very enlightening letter written by Mr. Clarke saved by Letters of Note (an excellent online resource for all sorts of obscure letters, memorandums, etc.).

He may also have been the first person to propose satellite communications, in a 1945 article in the ‘Wireless World’ magazine, though I do not have acces to the original source to confirm.

A bit of imaginative thinking married with practical technical knowledge goes a long way it seems.