Three-Toed Sloth

Books to Read While the Algae Grow in Your Fur, July 2022

Attention conservation notice:: I have no taste, and no qualifications to opine on the Italian Renaissance, political philosophy, intellectual history, or even game theory.

Niccolò Machiavelli, Selected Political Writings: The Prince, Selections from The Discourses, Letter to Vettori (edited and translated by David Wootton)

I have, of course, no qualifications to opine on translations of Machiavelli, but having worked my way through a fair number of versions of The Prince over the years, this is easily the most-readable one I've run across. (Wootton's introduction, in particular, is a remarkable production in its own right --- I'd say more but I don't want to spoil the effect!) It would be easy to treat these works as mere documents, artifacts illustrating a dead past, of merely-historical relevance. This translation makes them feel remarkably like a part of arguments we could be having right now, maybe are having right now.

Admittedly there is a cost to this --- when Wootton has Machiavelli use contemporary expressions like "political mechanism" or "social structure", I for one am curious about what the actual phrasing was. (If it really was "political mechanism", that'd be very interesting for the history of mechanism, so I suspect it wasn't.) But if I truly cared about that, I could consult other translations, or for that matter the original text. And the difficulties of trying to be more word-for-word literal are well-illustrated by Wootton's practice of parenthetically marking every place where Machiavelli used virtù (or one of its derivatives --- on p. 191 alone this has to be translated as, variously, "skill", "effect" and "will-power".

One thing reading this leaves me pondering is how to interpret The Prince: when (if ever?) was he speaking sincerely; when was he being ironic; when was he unmasking hypocrisy by plainly describing what his contemporaries were doing* (in a spirit I might characterize as somewhere between "I learned it from you" and "you say you want results, I'll tell you how to get results"); when was he using coded, "Aesopian" language to talk safely about dangerous matters; and when was he trying to make himself appear useful to dangerous gangsters and blasphemous grifters in the hopes they'd give him a desperately-needed job? (These are not mutually exclusive and I can well imagine him being especially pleased with himself when passages worked in multiple ways at once.)

The Discourses, by contrast, seem much more straightforwardly sincere. (Unless: maybe that's just what he wanted us to think!) But I will just mention two things which intrigued me. (1) I presume it's well-known to scholars, but new to me, that the famous opening to Gibbon's Decline and Fall about the age of the Antonines is clearly ripped off from elaborating on book I, chapter 10 of the Discourses. (Except for the bits in Gibbon about religion, which are from Machiavelli's book I, chapter 11.) (2) Has anyone written a good comparison between Machiavelli and ibn Khaldun, especially their ideas about institutions, personal character, and cycles of political founding, decay and re-formation? It's very interesting to see two inheritors of ancient political philosophy trying to found a generalizing science of politics based on historical examples, and I'm equally intrigued by the similarities and the differences. (Virtù is not how you say 'asabiyya in Italian, and neither is arete, but...)

This concludes this episode of my nattering about books I am not entitled to judge. §

ObLinkage: Previously on Wootton on Machiavelli.

*: Thus on Ferdinand of Aragon, ch. 21 begins "if you think about his deeds, you will find them all noble", but by the end of the paragraph, "exploiting religion, he practiced a pious cruelty, expropriating and expelling from his kingdom the Marranos: an act without parallel and truly despicable" (pp. 67--68).

Alain Bensoussan, Jens Frehse and Phillip Yam, Mean Field Games and Mean Field Type Control Theory

Mean field games are ones where each player's payoff depends on the distribution of states (or actions) across the other players, not on what any particular individual does. There are some interesting mathematical questions which arise when we consider the limit of an infinitely large population. (Each finite-dimensional individual then confronts the results of their joint actions as an alien and infinite-dimensional force.) In particular, the way large-but-finite-population games converge on infinite-population limits is related to some convergence issues in a long-simmering project, so I have been trying to educate myself about this topic. As part of that self-education, I have tried to explain my current understanding of mean field games more fully in another place.

This short book from 2013 is intended as a sort of crash course in mean field games (and the related mean field control problems). It presumes a lot of familiarity with mathematical control theory, partial differential equations and stochastic differential equations, but less with (e.g.) convergence of stochastic processes or even conventional game theory. In common with, it appears, most of the literature, it limits itself to settings where agents' internal states and exterior actions are all continuous, but it does consider both a single homogeneous population of agents, and the setting where agents are separated into a fixed number of discrete types (with the population of each type going to infinity together). It was useful for my purposes, which was giving me some orientation to the literature, but I imagine there must be better introductions now available.

If you are the sort of person who finds this intriguing, the odds are very good that you have access to the electronic version from the publisher, which is honestly probably all you need. §

Don S. Lemons, An Introduction to Stochastic Processes in Physics

This is very much intended as a first book on probability and stochastic processes for physics undergrads, and as such I imagine it'd work pretty successfully. I stopped being a physics undergrad 29 years ago, and will review the book for teachers of this material, not learners. (I.e., I won't explain common jargon.)

Lemons starts with very basic discrete and continuous distributions, spends a lot of time on Gaussians and moment generating functions, including a sketch of using moment generating functions to derive the central limit theorem. He then tries to describe continuous-time Gaussian processes, specifically the Wiener process and the Ornstein-Uhlenbeck processes. The viewpoint is essentially: take a deterministic ordinary differential equation, of the kind we know and love from physics courses, and throw a random-variable term into the right-hand side, i.e., more or less the way Langevin proceeded Back in the Day. (Langevin's key paper is included in translation.)

Lemons does a remarkable job of "solving" such stochastic differential equations by assuming that the solution is a Gaussian process, so all that's needed are the first and second moments as functions of time; getting ODEs for those moments; and solving those ODEs. It is, in short, a heroic attempt to act as though the theory of stochastic processes stopped with Chandrasekhar 1943. (The name "Ito" does not appear anywhere in the text.) Now, in deriving his solutions, Lemons pulls off some tricks which make me think that (unlike some physicists writing about stochastics) he does know Ito calculus, but doesn't mention it explicitly lest he be prosecuted by his less enlightened fellow tribesmen so as to not frighten off the children. I hesitate to say that this is unwise --- I presume that it's worked pedagogically for Lemons --- but what is unwise is not letting the reader know that there is a more advanced, i.e., both more flexible and more internally consistent, theory of SDEs, a theory which is certainly within the ability of physicists to master. (Cf.) In fact, I think that if Lemons had tried to teach Ito calculus to larval physicists, he'd have done a good job, which exaggerates my disappointment.

Over-all, if I had read this when I was in the intended audience, it would probably have done me a lot of good, but now I think my main use for this will be to mine it for examples to use as homework problems the next time I teach SDEs. §

Steven Cassedy, What Do We Mean When We Talk About Meaning?

I have struggled with the expression "meaning of life" for as long as I can remember, because I can't understand how "life" can be something like a message or a sign that means anything (outside of some very special circumstances). Cassedy is similarly puzzled: the way he puts it (I paraphrase a little) is that if someone could say "the meaning of life is X" (not that most people ever fill in X), one should be equally able to say "life means X", and, well, life is not a message or a sign. By a slight extension of this original sense, "meaning" also conveys "intention, purpose", and one could make sense of "the purpose of life is X" or "life is intended to do X", though it raises the question of whose intention or purpose.

What Cassedy does in this book is try to trace the history of how the phrases, and the ideas, of "the meaning of life" and "a meaningful life" became so ubiquitous in English and other languages. The starting point is Greco-Roman and Hebrew antiquity, where, he argues, there is simply no such concept. He then traces its pre-history, through the Christian fathers (especially Augustine) and the early modern period. "The meaning of life", he argues, first emerged in German, in the Romantic period, and spread from there, into English, French and Russian. (He has a convincing-to-me discussion of the German word involved, Sinn, but since my knowledge of German mostly relates to linear algebra and public transit, I am not competent to judge.) The phrase got further popularized in English through translations of the great 19th century Russian authors, especially Tolstoy and Dostoyevsky, who were of course influenced by the German usage. (Again, Cassedy goes over the history and usage of the Russian words translated as "meaning", but I know no Russian at all.)

Finally, he locates the real tipping point in post-war America, in the writings of the immigrant German theologian Paul Tillich, where "meaning" became a way of talking about God without having to affirm, or even explicitly mention, traditional supernatural dogmas --- but also without denying them, either. At the present, he concludes, it is the very slipperiness of "meaning" which makes it so ubiquitous: if people had to spell out exactly what they were trying to say, it would be less effective (and they might realize they don't know themselves what they're saying).

I found this fascinating and drily funny, but then I'm philistine anima-blind reconciled to living in a blind, purposeless universe, the fortuitous product of the concourse of atoms and void, where I get to be one of those safely on shore watching storms at sea lucky enough to not need this particular analgesic. §

Lauro Martines, Power and Imagination: City-States in Renaissance Italy (New York: Knopf, 1979)

This is a learned and gracefully written book which goes into a lot of the details of how Italian city states --- mostly but not exclusively north of Rome --- formed, struggled, were run, and eventually got absorbed (for the most part) into larger polities. I learned a lot about the internal political machinations, especially about institutional devices which, whatever their republican intentions, ended up helping to perpetuate oligarchy. Thus the "power" part.

The "imagination" is the high culture, especially art and humanism. Martines, for his part, sees this as ideology, and ideology in the service of upper class interests. While a lot of that is convincing, there do seem to be two gaps in his argument there. One is that he never grapples with why this art continues to be meaningful to people all over the world, centuries later, in ways which earlier and later art, equally in the service of related upper classes, just isn't. (Cf.) He does, to be fair, raise the parallel issue with humanistic scholarship, and says that the humanists made some "objective" discoveries of lasting value, but doesn't address how that was possible in a basically-ideological enterprise. The other defect, which I suspect is related, is that he doesn't really explain why serving upper class interests in this time and place should have required such an astonishingly large amount of innovation in technique. He's certainly aware of it: his first two pages of illustrations contrast a Florentine painting from the 1270s (basically still Byzantine) with one from 1426 (that might as well be from another world), and he has perceptive things to say about the development of artistic and literary styles. But these two issues --- why there was so much artistic and intellectual innovation, and why we still value the results --- are just not things he really tries to explain.

In the end, Martines gives the impression that he thinks of his subjects, the upper classes of the Italian city states, extraordinary but also horrible, and I can't help think that by the last chapters he was somewhat sick of them, and that in describing the Italian wars that began in 1494 he was (as the saying goes) "rooting for injuries". If so, it's hard not to sympathize. §

(I have not seen the paperback edition [Baltimore: Johns Hopkins University Press, 1988], but I can't find any indication of revisions.)

Fernand Braudel, Out of Italy: Two Centuries of World Domination and Demise (translated by Siân Reynolds from Le Modèle italien [Paris: Éditions Arthaud, 1989], but first published in Italian {Torino: Giulio Einaudi Editore, 1974])

I picked this up because I ran across a cheap copy and had been impressed by my earlier exposure to Braudel. This is wide-ranging and amiable, but I ended it with no clear idea of what Braudel was trying to argue, and very confused by what, exactly, he meant when he referred to something as a historical "problem" --- and he talks about problems incessantly. (And he's weirdly confident about what he knows are exceedingly tenuous estimates of economic conditions.) I half suspect the key to the book is a seemingly throw-away remark in the last chapter that "Everyone thinks for instance that 'France under the Sun King,' Louis XIV, was 'greater' than Francce under de Gaulle, but the 'inferior' France of the 1960s had a population two or three times greater and was many times richer". In conclusion: maybe worth reading if you are studying Braudel himself (or mid-20th-century historiography, etc.). Yes, I fully realize just how presumptuous it is of me to say such a thing. §

Books to Read While the Algae Grow in Your Fur; Writing for Antiquity; Philosophy; Enigmas of Chance; The Dismal Science; Physics