What’s best

Ian Hacking

  • The Nature of Rationality by Robert Nozick
    Princeton, 226 pp, £19.95, August 1993, ISBN 0 691 07424 0

Robert Nozick has a unique place in the annals of rational choice theory: he refuted it. Or so say I in my role as the last of the true Popperians. That was back in 1969. But now the mature philosopher is out to turn the theory into, not exactly a transcendental reality, but something implanted deep in the minds of some, if not all, human beings who have been sculpted by Darwinian evolution. This is an ideological book, concluding with evolutionary premises implying a complacent vision in which something like our present social order arose out of biological facts. The book begins, innocently enough, with technical questions about making reasonable choices. I’ll follow Nozick up that garden path, which is wonderfully landscaped, fresh and fragrant. But I’m giving warning now that I’m afraid of the ogres at the bottom of his garden.

Two principles form the pillars of the abstract analysis of rational choice theory. The first says that if one action has more desirable consequences than any other, no matter what happens now or in the future, then that’s the right thing to do. It is dominant, as they say in the rationality business. That doesn’t merely seem self-evident, it is self-evident, or so most readers will say to themselves. The second principle needs a little cultivation, for it is best put in terms of probabilities. In one version, when you are uncertain what will happen, you should perform the action that would be most rewarding on average, if you were presented with the same choice on many occasions. There are many ways to state this idea without recourse to averages; all use versions of a technical concept called ‘expected value’. This principle of maximising expectation may need qualification to allow, for example, for people who are averse to taking risks: it may seem better to keep what you have, rather than risk losing some of it even though in the long term you should end up better off. It seemed obvious that these two principles are mutually consistent; Nozick, however, showed that they aren’t when, long ago, he published a counter-example, a case in which the two contradict each other. He says that it was invented by a physicist, William Newcomb, but if one thinks of refutation as a public event, than all honour goes to Nozick. He showed exactly how the two principles come into conflict, and briskly swept away all easy solutions. It would take most of a column to state Newcomb’s paradox properly, so I won’t do it here (anyway it makes me slightly nauseous, as good antinomy should). You’ll have to go to the book, where Nozick once again displays his extraordinary skill at combining precision and a light touch.

I dare say there have been hundreds of published stabs at the problem, a good many of which have increased our understanding of rational decision. That is the point of paradoxes: harsh confrontation, painful rethinking, new speculation, trial and lots more error. No one has offered a solution that satisfies more than a handful of immediate cronies. Part of the trouble is that anyone who has any interest in rational choice theory wants both principles, dominance and maximising expectation. Most theorists want to ignore the issues. There may be an interesting group of examples of Newcombian situations (elegantly developed by Alan Gibbard and William Harper in another classic study), but it is not infectious. Most decision problems don’t catch even the germ of an inconsistency. For the logician, however, such monster-barring (to use a catchy phrase of the late Imre Lakatos) is not just a dishonest ‘don’t look now, avert your eyes’; it also prevents us from learning from conflict.

So we’ve all waited to see what Nozick would come up with after more than two decades. The answer is, sweetness and light. Why, asked some of his students, is everyone so passionately convinced that one of the two principles is right in its essentials, while the other is wrong? Can’t we have both, so long as we strike a balance in the rare troublesome cases? Moreover, Newcomb’s problem as formulated involves prizes of very substantial sums of money. Our so-called intuitions about which principle to follow seem to vary as we vary the sums of money, so that one principle is more attractive when there is a lot at stake, in one situation, while the other principle is more attractive for other stakes in a slightly different situation. So why not balance the two, taking into account the stakes? Nozick in effect proposes a formula that does just that. It allows for a continuum of decision rules, leaving a choice to the person making the decisions. If you favour one rule in almost any situation of conflict, then you are at one end of the continuum, while if you favour the other, you are at the other end. Nozick, we infer, is somewhere in the middle.

Give and take is a good maxim for getting along with other people, or peoples. Is it also good for removing intellectual confusion, or for making up our own minds? Nozick cites a discouraging precedent for his continuum. In 1952 the best remembered logical positivist, Rudolf Carnap, published a booklet about probability called The Continuum of Inductive Methods. There were, he said, infinitely many ways of making predictions about the future, ranging from those that jumped to conclusions to those that paid no attention to any evidence whatsoever. A rational person was to find a comfortable point on the continuum and act accordingly. That was the last gasp in a project to solve Hume’s problem of induction using a logic of probabilities. It had begun with grand hopes in work by Maynard Keynes, his teachers and his contemporaries. It expired largely thanks to Carnap’s unceasing toil. Even he may have known that his continuum was a dead end. I saw him only once, in 1965, when I had the honour to have him among the audience of one of the first public talks I ever gave. I made some characteristically sophomorish remark about his 1952 book. He ponderously rose and began: ‘I don’t remember what I said in that book but ...’

The unfortunate company he keeps doesn’t show us anything about Nozick. But his response to Newcomb’s problem does seem to show something about the development of his work. His doctorate was on The Normative Theory of Individual Choice (1963) i.e. it was about the themes to which he has now returned as a mature philosopher. He became deservedly famous, however, for his sparkling libertarian tract, Anarchy, State and Utopia (1974; USA backwards, when you come to think of it). His lengthy Philosophical Explanations (1981) is a deeply original and reflective study of traditional philosophical problems. It uses the best current ideas of philosophical analysis, and is plainly written for the serious general reader, free of both jargon and condescension. Most philosophy books plonk out of the press and into a few hands; some are noticed in this and other highbrow periodicals. Nozick’s then publishers intended to change all that. They mounted a coast-to-coast publicity tour, interviews, talk shows, hotel rooms filled with fruit and flowers, or so I read in the newspapers. That was a tribute to Nozick’s ability to make hard philosophy accessible to the general reader. After that, The Examined Life (1989) was a mellow reflection. The vigour of libertarian self-interest had been transformed into gentleness and gentility. Where a footnote in Philosophical Explanations had appeared to speculate that certain yogic postures for gentlemen were intended to enable them, at the limit, to engage in oral masturbation, we were now modestly told that the examined sex life should go in for variety.

This progress has been an affair of intellectual grooming, from which in many respects the reader benefits wonderfully. The 35 pages of notes at the end of The Nature of Rationality are quite the most judicious and interesting guide through almost everything readable in rational choice theory. Other reviewers have noticed Nozick’s cornucopia of suggestions about most topics in the field – as if he were laying out endless projects for future research. But the point is different, surely. Nozick is a distinguished teacher. He tries to involve the reader, fixing issues in the mind by saying: ‘I don’t quite know what the answer is, but look, you too can think about these things, here’s how.’ Yet for all that, most of his suggestions have a kind of placid generosity about them that leaves me cold.

For example: everybody knows that the calculations hitherto favoured by rational choice theory give little room to most human values and interests. Nozick concludes that we ought to represent these values within the theory. Actions mean things to us over and above their direct consequences; we should add to our calculus the notion of symbolic utility. All sorts of complications then arise, and new puzzles present themselves: which is good. An immensely richer analysis of rational thought will emerge. Or will it? Cynics will say that the attempt to make the theory more all-embracing is exactly the wrong thing to do. Rational choice theory is grounded in exchange values, which we can represent in the coin of the realm. We don’t want to make our moral life more mercantile. But this cynical reaction is inapt; it does not take sufficiently seriously what rational choice theory is good for.

The theory has two great roles. First, it may enable a corporation (it could be you, incorporated, but more likely a group of you) to reach practical decisions when you can rate the options and their consequences by, in effect, money – and when you can scale your guesses about what will happen by, in effect, probabilities. It is a way for members of the corporation to put their competing opinions into one hopper and, without schism, make a firm decision. Rational choice theory is a device for the resolution of internal conflicts.

Its second role involves external conflict. It is integral to a democracy whose members or sub-groups have different interests, different knowledge, and principled disagreements about what to do. It may be a neighbourhood association trying to redesign traffic flow, or the town council addressing the same issue. It may be a plan to cut national deficits or rescue a failing system of national health insurance. Bureaucratically institutionalised principles of rational choice need not provide a way to reach the best or right decision, so long as they furnish a way to decide without apparently leaning in anyone’s favour. If you think I’m trying to put rational choice theory down, see it this way: the theory takes on the role of Hobbes’s Leviathan, a sovereign that prevents us killing each other – a very notable achievement. Dictators don’t need rational choice theory: they just decide. For a historical confirmation, consider that the most brilliant theorists of the foundations of axiomatic probability theory were tsarist and then Soviet, while applied probability and decision theory is a product of people of comparable mathematical prowess living in liberal democracies.

Our types of society need to have agreed protocols for making what we perceive as reasonable decisions. Rational choice theory provides a structure that keeps us on the rails. It is irrelevant whether the choices made according to the theory are rational according to some transcendental vision of absolute rationality. The theory provides us with a way of getting on, even when hard decisions must be made. This is to see rational choice theory as a cultural phenomenon. That does not mean there is no transcendentally rational solution to difficult problems, it means that is not the point. Again, compare Hobbes’s sovereign. The sovereign could be a philosopher-queen, for all Hobbes cares, who made the wisest decisions according to the scheme of absolute moral value. But that’s not why the sovereign should be obeyed.

Nozick may not be so far from this vision, but with one radical qualification. He sees himself as discussing the Very Nature of Rationality – where rationality is not transcendental but a product of evolution. It is curious how time and again since Darwin we have engaged in nature/nurture controversies. Nozick is at one with nature, evolution and innateness. Certainly he acknowledges culture and history too, but they are responses to biologically evolved instincts of rationality. Alluding to Max Weber, he writes that ‘economic and monetary calculations, bureaucratic rationalisations, general rules and procedures came to replace action based on personal ties, and market relations were extended to new arenas. Rationality, together with related institutional changes that explicitly utilise and depend upon rationality, has brought many benefits and enabled rationality to extend its domain even further.’ Rationality sounds like a force. Of what? It is something that has evolved in us. What evolved is not just the ability to reason, to talk, but an unusually explicit mode of thought, namely rational choice theory.

Evolution becomes almost personified in the course of the book. What Nozick sees as conflicting intuitions about how to resolve this or that delicate dilemma in rational choice theory are thought to have evolved in an almost biological way; they are adaptive. We’re not now speaking of defining characteristics of humanity – that we walk upright, have languages – but of the very special conflicting analyses of decision theorists, postulates that in many cases no human being ever thought of until recently. There is no indication of the mechanisms for this selective evolution of what seem to be local cultural practices.

Moreover, rationality, at least in its higher forms such as the ones Nozick contemplates, turns out to be no more a human universal than skin pigment. The institutional changes associated with Nozick’s rationality have, he says, ‘made the world, in various ways, inhospitable to lesser degrees of rationality’:

Within Western societies, the balance has shifted in the division of traits that served in hunter-gatherer societies. Rationality first was able to extend its sway by bringing benefits to other traits too, but the other traits became more dependent on rationality, and rationality became more powerful and subject to fewer constraints. Rationality is proceeding now to remake the world to suit itself, altering not only its own environment but also that in which other traits find themselves, extending the environment in which only it can flourish ... Traits that were once of co-ordinate importance are placed in an inferior position. This presents a challenge to rationality’s compassion and to its imagination and ingenuity: can it devise a system in which those with other traits can live comfortably and flourish ... with the opportunity to develop their rationality if they choose – and will it?

Got it? Those with hunter-gatherer traits like the potential for fast sprinting, for example? In the last paragraph of the book, quoted in advertisements because it sounds so rich and moving, Nozick writes that ‘our rationality, both individual and co-ordinate, defines and symbolises the distance we have come from mere animality.’ Sounds terrific! Do the publishers realise that it appears to follow from that clause, plus the paragraph I’ve quoted from the facing page, that some peoples are closer to animality than others?

I’m not here worried by Nozick’s political incorrectness (though I’m worried that no reviewer I’ve come across – the book has been out for some time now – has mentioned this readily noticed inference). I’m worried because I see no reason to believe that the subtle but sometimes conflicting intuitions about rationality that Nozick so lucidly discusses can have been produced by evolutionary pressure. It is that premise I doubt. Don’t focus on the conclusion, which you may or may not like. Focus on the argument, and its premise.

Yet Nozick has once again done us a favour by directing us, in a slightly veiled way, to the conclusion. For there’s a lot of social-evolutionary talk right now, quite as much as there was a century or so ago, and with a similar ideological bent. Nozick’s book reminds us how this talk, ungrounded in any mechanisms known to biological science, is part of a power play, a vast attempt at legitimation. Just look at the extraordinary slide we see in this book. We pass from technical discussions of paradoxes and dilemmas within a rigorous formal theory, to a hypostasised entity, rationality, that is out there ‘extending its sway’ (swaying not the mind but the world order). This entity is biological, the product of evolutionary struggle. There is a stupendous is/ought move here. Rationality is – well – rational. It’s about right decision, reasonableness: that’s value. Evolution is where we have got to: that’s fact. So we have got to what’s right. We who have arrived at a free-market economy have not invented another of the varied cultural forms that so characterise the amazing creativity of our socially imaginative species. The present dominating cultural form is presented as inevitable, contingent only on the course of neo-Darwinian evolution itself. We may make a mess of everything, creating a world intolerable to our own symbolic utilities, but we do have the best tool to hand: rational choice theory, as honed by rationality itself. We (we, the most rational ones, not you out there) are engaged in a biologically ordained mastery of the universe and its denizens.