On Hedgehogs, Koalas, and Other Animals

Outside academia, Isaiah Berlin is probably best known for his distinction between “foxes” and “hedgehogs” based on Archilochus saying that “the fox knows many things, but the hedgehog knows one big thing”.1 When I first encountered a reference to this distinction I assumed that it had something to do with broad versus narrow knowledge or learning, with the Renaissance/​Enlightenment ideal of the homo universalis (or polymath) versus the academic (hyper-) specialist, or with Thomas Aquinas’s fear of “a man of one book” (homo unius libri), that is, someone who knows one book/​thing really well, but doesn’t know much else. I was wrong.

Hedgehogs, in Berlin’s view, “relate everything to a single central vision, one system, less or more coherent or articulate, in terms of which they understand, think and feel – a single, universal, organising principle in terms of which alone all that they are and say has significance”. Foxes, on the other hand, “pursue many ends, often unrelated and even contradictory, connected, if at all, only in some de facto way, for some psychological or physiological cause, related to no moral or aesthetic principle”. Foxes “lead lives, perform acts and entertain ideas that are centrifugal rather than centripetal; their thought is scattered or diffused, moving on many levels”.2 A few more sentenced intended to describe foxes follow, but they only make Berlin’s distinction (even) more obscure.

At first glance, the distinction seems to make sense – people who know many things, versus people who just know one big thing – but the more Berlin says about it, the less sense the distinction makes. There are some apparently contrasting keywords that appear on the two sides of the distinction, but a closer look shows that those keywords apply to different things and thus do not oppose the two categories. One versus many – but the hedgehog adheres to one principle or system and the fox has many ends or goals. Coherence versus contradiction – but the hedgehog prefers a coherent system (again), while the fox may have contradictory goals. These are not at all mutually exclusive. It is quite possible to have multiple contradictory goals and a single vision at the same time (or a manifold, incoherent vision and a single goal).

If we add what Berlin doesn’t say explicitly, but what can (perhaps) be read between the lines, then the difference seems to be one of thinking styles: a hedgehog’s thought is targeted and systematic, while a fox’s “thought is scattered or diffused”. But if that’s what the distinction is about, then I suspect that we are all hedgehogs some of the time and foxes at other times.

Or perhaps, the defining criterion is that hedgehogs relate everything to a single, more or less coherent system or central vision, and foxes don’t. Probably “everything” shouldn’t be taken overly literally here – Berlin mentions writers and philosophers and “everything” refers to their work as such. This still doesn’t make the distinction much clearer, however. Take Donald Davidson, one of my favorite philosophers, as an example. I would say that there is a single idea uniting most of his philosophical output, even if he described that single idea in different terms throughout his work (“interpretation”, “triangulation”, “ostensive learning”, and so forth), and he has hinted at this himself as well. But his work just concerns a relatively small corner of philosophy, and I’m sure that he would never have claimed that literally everything should be (or could be) made to fit with that idea. So, if Davidson would count as a hedgehog, then “everything” just refers to whatever a hedgehog happens to be working on. A hedgehog, then, is someone who aims to relate everything within their area of research (or something like that) to a single, coherent vision. I suspect that by that standard, all scientists and most philosophers are hedgehogs. (Even if they may sometimes switch one vision for another. Or several times even, as in case of Hilary Putnam.) And for that reason, understood this way, the hedgehog/​fox distinction does not seem particularly useful.

As mentioned above, when I first encountered the distinction (in some other text) I had the impression that it was about generalists versus specialists, and as far as I can see, I’m not alone in making that mistake. In hist recent bestseller, How the World Really Works, Vaclav Smil, seems to interpret the distinction like this as well, for example.3 He writes:

Rather than resorting to an ancient comparison of foxes and hedgehogs …, I tend to think about modern scientists as either the drillers of ever-deeper holes (now the dominant route to fame) or scanners of wide horizons (now a much-diminished group). Drilling the deepest possible hole and being an unsurpassed master of a tiny sliver of the sky visible from its bottom has never appealed to me. I have always preferred to scan as far and as wide as my limited capabilities have allowed me to do.4

Philip Tetlock also interprets the distinction as one between generalists and specialists, but with an important twist. In his Expert Political Judgment, he writes that:

If we want realistic odds on what will happen next, coupled to a willingness to admit mistakes, we are better off turning to experts who embody the intellectual traits of Isaiah Berlin’s prototypical fox – those who “know many little things,” draw from an eclectic array of traditions, and accept ambiguity and contradiction as inevitable features of life – than we are turning to Berlin’s hedgehogs – those who “know one big thing,” toil devotedly within one tradition, and reach for formulaic solutions to ill-defined problems.5

Notice that Tetlock also mentions “contradiction”, but while Berlin’s foxes have contradictory goals, Tetlock’s foxes recognize “ambiguity and contradiction as inevitable features of life”, or in other words, that the world around us is a messy place. And Tetlock’s hedgehogs seem to be considerably more fanatical about fitting literally everything in the same mold or principle than Berlin’s – they are not just specialists, but specialists who believe that their specialty applies to (almost) everything (or specialists who mistake themselves for generalists). (Mainstream economists are exactly Tetlock’s hedgehogs, by the way, but there may not be that many other examples.) Hence, Tetlock’s hedgehogs and foxes are not the same as Berlin’s, and (probably) not the same as Archilochus’s either. Nevertheless, Tetlock’s hedgehogs may be more similar to Berlin’s than to the interpretation of hedgehogs as mere specialists.

The vagueness and divergent interpretations of the fox/hedgehog distinction make it rather useless. Dependent on how it is interpreted, I am definitely a hedgehog, definitely a fox, somewhere in between, a bit of both, or something else entirely, and I suspect the same would be true for many others. In any case, despite the distinction sometimes (perhaps, often) being interpreted as being about the generalist/specialist distinction, it’s not that. Foxes are not just generalists, and hedgehogs are not just specialists, so let’s introduce some further animals.

National Geographic defines generalists and specialists as follows: “Generalists can eat a variety of foods and thrive in a range of habitats. Specialists, on the other hand, have a limited diet and stricter habitat requirements”, and suggests raccoons and koalas as prototypical generalists, respectively specialists. Raccoons can survive and thrive in very many different kinds of environment, while koalas can only eat the leaves of one particular kind of tree. If a koala would behave like Tetlock’s hedgehog, it wouldn’t just fail to understand its own specialism, but would even fail to realize that there are circumstances or environments in which that specialism is useless or inapplicable. A koala-as-hedgehog would venture into the ocean or desert unfazed, assuming that there are plenty of eucalyptus leaves for it to eat there. (Real hedgehogs don’t behave much like Tetlock’s hedgehogs either, by the way – they are probably closer to raccoons.)

It should be fairly obvious that the generalist/specialist distinction is not a dichotomy, but a spectrum. Like koalas, giant pandas are extremely specialized, but red (or lesser) pandas seem to be marginally more flexible with regards to foods and habitat. And while koalas (and giant pandas) might be close to one end of the scale, raccoons certainly do not occupy the other end. Raccoons can live and thrive in relatively many environments, but certainly not in all. The animals closest to the generalist extreme are humans, but since it would be confusing to have humans as a metaphor for humans, it’s probably better to pick another animal that shows extreme flexibility and adaptability. Rats may be a good example.

The sciences are dominated by koalas and red pandas. The growth of scientific knowledge and the need to publish have made (hyper-) specialization a necessity in science. But there are some raccoons as well. Vaclav Smil, already mentioned above, seems a good example of a raccoon. The anthropologist David Graeber, co-author another recent bestseller, The Dawn of Humanity, was also more raccoon-ish than koala-ish.6 Actually, many science books written for a general audience are far removed from the paradigmatic koala. Books by David Wallace-Wells and Mark Lynas that summarize research in many branches of climate science look quite raccoon-ish as well, for example, even if they are really about just one topic.7 Slightly more raccoon-ish is Bill McKibben’s Falter, which also discusses other threats to humanity, and thus broadens the scope a bit,8 and Sean Carroll’s The Big Picture, as the title already suggests, is an even more Raccoon-ish science book for a general audience.9 This list of examples could easily be extended.

On a side note, while the idea that it was still possible a few centuries ago to become acquainted with most or even all of Western science and philosophy, is quite widespread, notice that this claim is almost always made without the “Western” qualification. That is, the more typical claim is that it was possible two or three centuries ago to be reasonably acquainted with all scientific and philosophical knowledge, but invariably, in such claims “all … knowledge” refers to all Western/European knowledge and doesn’t include Indian and Chinese philosophy, for example. In other words, the suggestion that the homo universalis ideal was still possible a few centuries ago is almost always based on the racist assumption that all “real”/worthwhile knowledge is Western.10

Nevertheless, even if these books are written by scientists and journalists who are more like raccoons than koalas, they are certainly far removed from the ultra-generalism of the metaphorical rat. (If the rat is an ultra-generalist indeed. I’m not so sure, actually, but let’s stick with it.) One may wonder whether this is even possible. Two or three centuries ago, it was still possible to become acquainted with most of Western science and philosophy, but that certainly isn’t the case anymore. The Renaissance/​Enlightenment ideal of the homo universalis may no longer be an attainable ideal. And if that’s the case, rats went extinct two centuries ago or so. So, there are no rats, or no successful ones at least.

Expanding our zoo a bit further, let’s try to make some space for the weasel. Weasels “are fierce carnivores with a confidences and audacity out of proportion to their stature”.11 They are famous for attacking prey much larger than themselves. They also sometimes attack birds larger than themselves, which doesn’t always end well. The bird might kill and eat the weasel instead, or dive into deep water and drown it, or the weasel might kill the bird in mid-air and fail to survive the subsequent drop. Carolyn King has called this risky behavior “weasel roulette”.12 The weasel’s domesticated relative, the ferret, doesn’t seem to have much understanding of relative size either.

The point of introducing the weasel is that trying to be a rat (and perhaps, even a raccoon) is – in some sense – a bit like being a weasel, albeit possibly a very stupid one. A weasel sometimes takes too much risk in attacking a prey that is too big and/or dangerous for it to handle. Trying to be a rat is like that. Again, a couple of centuries ago, one could still aim to be a homo universalis with reasonably in-depth knowledge of very many (or even all) branches of science and philosophy, but nowadays, even trying to gain in-depth knowledge of all of physics, or psychology, or history, and so forth is virtually impossible, let alone several of them. A weasel tries anyway. Or something like it. Or more broadly, a weasel tries to tackle something that is much too big for its size.

A weasel suffers from something like the Dunning-Kruger effect – it doesn’t understand its own limitations. Or if it does, it ignores them, or pretends to be unaffected by them. The term “Dunning-Kruger effect” refers to the phenomenon of people having so little knowledge or understanding of some area that they don’t even realize how little they know or understand, which leads them to believe that they know/​understand a lot more than they really do. So, a flat-earther might believe that she understands physics and geography, because she really has so little knowledge of these fields that she doesn’t even realize her own ignorance. Similarly, a weasel trying to be a rat might have superficial knowledge of many areas,13 but insufficient in-depth knowledge to realize how superficial its knowledge really is, and thereby be tricked into believing that it knows a lot more than it really does. Or perhaps, the weasel just plays “weasel roulette” – it is aware of its limitations and that things may go sour, but it takes the leap and tries to capture the elephant anyway.14

The problem with weasels is that they might not really fit in our zoo.15 Modern science and philosophy are mostly made for and by koalas. They occasional raccoon is tolerated, but there really is no room for (or patience with) weasels. This is understandable from a historical perspective, but from that same perspective, one might also wonder whether we are losing something if we fail to make room for weasels.

It could, perhaps, be argued that many of the “great” philosophers and scientists of past ages were weasels. I’m thinking of people like Aristotle, Kant, Marx, Mozi 墨子, Newton, Vasubandhu, and (many!) others. Certainly, none of them were koalas, but they weren’t raccoons either. They tried to understand (almost) everything there was to understand and then contribute to that. They attacked the elephant, and brought it down – that is, they played weasel roulette and won. That’s why we remember them.

Actually, I don’t think this is right. If they were weasels, they were facing very different odds than today’s weasels. The “prey” they successfully hunted wasn’t all that large yet, while it is enormous now. And it is undeniable that the philosophers mentioned in the previous paragraph were very smart and very well-connected as well. (The latter should not be overlooked. One of the things Randall Collins has shown in his majestic The Sociology of Philosophies is that all major philosophers were exceptionally well connected across generations through teacher/student relations and within generations through relations of acquaintance and conflict.16) In other words, they really weren’t trying to catch out-sized prey at all (given both the size of the “prey” and the capacities and circumstances of the “predators”), and therefore, they weren’t playing weasel roulette. And as playing weasel roulette is what defines weasels here, this means that they weren’t weasels after all. Perhaps, they were raccoons at a time the “world” was still so small that raccoons could cover all of it. Or they were some other, yet unmentioned kind of animal.

But if this is right, then there may never have been much room for weasels in the zoo. I have little doubt that there have been some kinds of weasels throughout the history of science and philosophy – Wang Chong 王充 might be an early example, for example – but we might not remember many of them, and most of them probably made their home at the academic/​intellectual fringes of their time (like Wang Chong). Weasel roulette (of any kind) has probably never contributed much to scientific progress, and consequently, there is little reason to bemoan the zoo’s lack of hospitality for weasels. Weasels just don’t belong in the zoo. But then, where do the weasels go?

The thing with animals (like us) is that they can’t choose their species. A koala cannot suddenly decide to be a raccoon. (And even if it could, that decision wouldn’t actually change it into a raccoon.) Perhaps, the same applies to these animals as metaphors. Some of us may be a bit more hedgehog-ish (but remember that it is far from clear what exactly that means), others might be more like foxes, koalas, or raccoons. Or, indeed, like weasels.

I suppose that the fundamental attribution error applies here – or in other words, that it would be a mistake to attribute too much of this kind of differences to character rather than to circumstances – but there may be something like an individual predisposition to be more like a fox, or more like a raccoon, and so forth, even if different circumstances push one in different directions at different occasions. At least, I’m quite sure that I am a weasel and that I can’t be anything but a weasel. Most of my projects are weasel roulette: trying to capture an elephant while knowing full well it can’t be done (but pretending otherwise much of the time). And consequently, many of my publications are overly ambitious and littered with ignorant errors and oversights.17 And even when I engage in some more koala-ish (i.e. specialist) project it is always within the context of my big weasel projects (and a new and different kind of koala every time, it seems), and moreover, a kind of weasel roulette itself as I never have all the in-depth knowledge required. The problem is that I cannot stop being a weasel any more than that I can stop breathing. Or actually, that’s the only way I could stop being a weasel.

Presumably, there are others like me. Other weasels, but also other animals that don’t quite fit in the zoo. And from the perspective of the zoo and its inhabitants, that’s probably fine. Personally, I’m OK with that as well. Increasingly, I feel that that’s how it should be – indeed, I don’t belong in the zoo. But at the same time I’m curious about all the other animals that aren’t accepted in the zoo. Weasels might not belong, but that doesn’t mean that the entire zoo should just be populated with koalas, a few red pandas, and an occasional raccoon. Science and philosophy could do with a bit more variety. Real koalas are threatened with extinction, but a metaphorical zoo that is entirely populated with metaphorical koalas might not have much of a future either.

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  1. Isaiah Berlin (1953), The Hedgehog and the Fox: An Essay on Tolstoy’s View of History, Second Edition (Princeton University Press, 2013). Berlin quotes Archilochus on p. 1.
  2. Ibid., p. 2.
  3. Vaclav Smil (2022), How the World Really Works: A Scientist’s Guide to Our Past, Present, and Future (Viking).
  4. Near the end of the introduction.
  5. Philip Tetlock (2005), Expert Political Judgment: How Good Is It? How Can We Know? (Princeton University Press), p. 2.
  6. David Graeber & David Wengrow (2021), The Dawn of Humanity: A New History of Humanity (London: Allen Lane).
  7. David Wallace-Wells (2019), The Uninhabitable Earth: A Story of the Future (Allen Lane). Mark Lynas (2020), Our Final Warning: Six Degrees of Climate Emergency (4th Estate).
  8. Bill McKibben (2019), Falter: Has the Human Game Begun to Play Itself Out? (Wildfire).
  9. Sean Carroll (2017), The Big Picture: On the Origins of Life, Meaning, and the Universe Itself (Dutton).
  10. See also Is “Philosophy” Racist?
  11. Carolyn M. King (1991), “Weasel Roulette” Natural History Magazine 100:11 (November 1991): 34–41, p, 35.
  12. Ibid.
  13. In reality, weasels hunt and kill rats, so the rat metaphor is getting rather odd here.
  14. Ferrets (i.e. domesticated weasels) are hilarious. An excited ferret will attack anything (although this probably depends on character). I have little doubt that a sufficiently excited ferret would attack an elephant.
  15. If you hadn’t realized yet, the “zoo” refers to science and/or philosophy and/or the academic world.
  16. Randall Collins (1998), The Sociology of Philosophies: A Global Theory of Intellectual Change (Belknap).
  17. Take my last book, A Buddha Land in This World as an example – it meanders through several branches of philosophy (metaphysics, philosophy of language, epistemology, ethics, and so forth) as well as a few other sciences (economics, political science, climate science, history, and so forth) based on many years of study, and lists 1450 references. It hasn’t been enough. Almost every week I read something which makes me realize another mistake in the book. — Lajos Brons (2022), A Buddha Land in This World: Philosophy, Utopia, and Radical Buddhism (Punctum).

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