Philosophical Explanations
Robert Nozick
The Belknap Press/Harvard University Press, $25

There was once a chap who wanted to know the meaning of life, so he walked a thousand miles and climbed to the high mountaintop where the wise guru lived. “Will you tell me the meaning of life?” he asked.

“Certainly,” replied the guru, “but if you want to understand my answer, you must first master recursive function theory and mathematical logic.”

“You’re kidding.”

“No, really.”

“Well, then… skip it.”

“Suit yourself.”

That is the sad story of the encounter between twentieth-century analytic philosophy and the public. The philosophers, secretly relieved not to have to explain things to the uninitiated, turn back to their intricate scholastic exercises—usually forgetting that the point of those exercises was after all to answer the Big Question. And the public, having savored the thrill of just asking the Big Question, departs before the difficult answer can get rolling—like those tourists at Harrod’s who pose as serious shoppers for sterling tea services and then beat a hasty retreat, gratefully snapping up tiny souvenir jars of marmalade as they leave (“Well we had to buy something!”).

Some people must buy the junk found in the philosophy section of most bookstores, but most serious readers shrug off the whole field. Philosophers eventually learn to be neither surprised nor embarrassed by this. Very few people who proclaim an intense curiosity about ultimate philosophical issues really care enough to endure some trouble in satisfying it. So what? No doubt most people are quite justified in thinking either that they have more important things to do, or that they couldn’t do this important job well enough for it to be worth their effort. Unfortunately, however, those few who do care, those intrepid truth-seekers who are as ready to work for their philosophy as for their physics or biology, are often disillusioned by what they find in contemporary academic philosophy: a mandarin absorption in the technical merits and flaws of philosophical artifacts—engines of war deployed on a toy battlefield.

Robert Nozick, a professor of philosophy at Harvard, deplores this situation. His ambition in Philosophical Explanations is not only to address the Big Question in terms the amateur will understand (with effort) and the professional will respect, but at the same time to describe to his fellow professionals—and exhibit in the course of describing—how philosophy ought to be, and can be, done. If this aim seems a ludicrous example of chutzpah, shouldn’t a philosopher respond by pointing out that it is just what philosophers were always supposed to do?

In the last fifty years or so the sciences—even the social sciences—have largely usurped the former authority of philosophy. While a few philosophers, notably on the Continent, have gone on professing as if nothing had happened (and cutting rather preposterous figures), most philosophers, especially in the Anglo-American tradition, have covered their retreat from influence by representing themselves in a variety of more modest roles: as the canon lawyers of science and no-nonsense; as informal language-problem therapists; as discipline-critics; as harmless formalists (like mathematicians) tripped out on the intricacies of esoteric concept-architectures—useless but brilliant ornaments of the academic world. Thus comfortably redescribed, philosophers have in fact done original and valuable work, but few of them have been so bold as to attempt to demonstrate its value to the outside world.

Nozick, a master technocrat trained in the analytic tradition, brings the methods and results of that tradition (heavily supplemented) to bear on all the Big Questions: “Does life have meaning? Are there objective ethical truths? Do we have free will? What is the nature of our identity as. selves? Must our knowledge and understanding stay within fixed limits?” His patient and elaborate answers are not, of course, answers in the usual sense. He does not pretend to “tell the reader the answer” (anyone who wants a philosopher to do that isn’t serious about the questions in the first place) but rather, he attempts to get the reader to figure out with him why a certain set of answers to these questions is good, perhaps even the best answers available. This task is far from easy, but Nozick has worked very hard, unlike our mountaintop guru, to cajole the questioner with vivid examples, reassuring asides, and good humor.

His answers are well worth the effort it takes to understand them. They are much more interesting, even in their lapses, than most current work in philosophy; dazzlingly clever at times, but also wise; redolent of the great themes in the history of philosophy, but at the same time studded with original ideas and sophisticated to the highest contemporary standards; remarkably unified in spite of their broad eclecticism.

Nozick unfolds his grand design in a cunningly arranged sequence of increasingly sophisticated projects, building new structures out of the pieces he had earlier assembled for us. At their best, his explanations are marvels of lucidity and vividness, and one is tempted to hope that this is the book we’ve been waiting for: high-powered philosophy for Everyman. But at various points Nozick turns his back on this bold aspiration and reverts to the more self-indulgent course of talking to philosophy professors only. Few non-professional readers, I fear, will develop the momentum to carry themselves through these passages, but I urge them to try.

Nozick begins by renouncing a major tradition of philosophic method: argument-combat, or what he gently mocks as “coercive philosophy.” Why do philosophers think they should try to concoct winning arguments, knockdown proofs? Must philosophers be so aggressive? “Perhaps philosophers need arguments so powerful they set up reverberations in the brain: if a person refuses to accept the conclusion, he dies.” This strange ethos of our profession has never been fruitful; in spite of our aspirations to rigor there is not a single substantive result in philosophy that enjoys the unclouded reputation of the major theorems of mathematics or the vindicated hypotheses of the natural sciences.

What, though, is the alternative? Not proof but explanation, Nozick says, and he means to focus on a certain sort of explanation: bringing oneself to see just the possibility of something—free will, knowledge, meaning—in the face of powerful skeptical challenges. We shouldn’t try to refute the challenger (his views are his problem); we should satisfy ourselves that we can, with integrity, continue to believe what we want to believe. Won’t even this gentle goal involve us in composing traditional arguments—if only to convince ourselves of flaws in trains of thought we are resisting? Yes, and in spite of his avowal, Nozick presents many an argument, some of them as technically imposing—and tricky—as any to be found in contemporary philosophical literature.

Nozick also runs a presumably calculated risk in presenting the more convoluted of these arguments. If they persuade—or just impress—one academic philosopher for every ten outsiders who abandon the book in dismay, will Nozick think he has won his gamble? Though he has wisely packed off a good deal of the technical, specialized material into long notes at the back of the book, the considerable amount of very difficult reading that remains in the body of the text indicates, at best, questionable editorial judgment. Could he find no more accessible—but still honest—explanations?

The first major philosophical problem Nozick tackles is the nature of the self and the puzzle of personal identity. When I grow old and my body starts disintegrating from disease, is it possible in principle that I could survive by having my brain (with all its memories and plans) transplanted into a young, healthy body? If the answer is yes, what about the prospects of surviving if a detailed description of my brain(and, perhaps, the rest of my body) were used to make an atom-for-atom duplicate? Would the newly made person be me—or just a perfect twin? If the answer is that such a duplicate would not be me, is that because some golden nugget of self would fail to get transferred? For all its appeal, this is a highly dubious idea, unable even to do the job it was invented for. Science tells us that our cells are  gradually replaced over the years. Can there be anything more to continued personal identity than there is to the continued identity over time, surviving repairs and replacements, of such things as chairs and nations and ships?

According to an ancient version of this puzzle, the ship of Theseus can be rebuilt over time, plank by plank, and still retain its identity. But what if somehow all the discarded planks were gathered up and put back into their original configuration? Which ship would be the original? Here we seem called upon to make some sort of pragmatic, legalistic decision. All the relevant facts are in, and the remaining question is about the most judicious way of talking about them. The case of personal identity seems different, but Nozick builds a compelling case for treating the two cases in just the same way, by applying his “closest continuer” theory of identity: something y at a later time is the very same entity as something x at an earlier time if and only if “first, y‘s properties at t₂ stem from, grow out of, are causally dependent on, x‘s properties at time t₁, and second, there is no other z at t₂ that stands in a closer (or as close) relationship to x at t₁ than y at t₂ does.” There really is no simpler way of expressing this idea, and once one sees what is being said it may seem obvious or even trivial. Spelled out in detail, however, the claim is full of surprises—a fine example of philosophical rigor paying off, and hence a good way to start the reader off on a difficult book.

Nozick acknowledges that there is room to doubt if this “closest continuer” relation he has so carefully presented really is identical to the identity relation, and not just some closely resembling impostor. Well, but is it, perhaps, the closest instantiated relation—as close to a “perfect” identity relation as we can get? Nozick’s hypothesis is that the closest continuer relation is in effect the closest continuer of the identity relation.

This reflexive recursion, applying an idea to itself, is one of the major themes—and methods—of the book, as it was in Hofstadter’s Gödel, Escher, Bach (Basic Books). Again and again Nozick doubles back to show how some idea he has developed applies to itself. For instance, his proposal that we should abandon knockdown proofs in favor of a panoply of more or less independent and individually less conclusive persuasions is supported, most effectively, by just such a panoply. A number of writers in different fields have recently hit upon this idea, supporting it in various ways. It is often called the robustness of a hypothesis, and, putting two of Nozick’s themes together twice, we can note that robustness is as robust an idea as reflexivity is.

Nozick employs this strategy several more times in developing his views of the self. Nozick would like to explain why it is no accident that we care about ourselves. He attempts to show both that a being who could care about anything would have to care about itself, and that only a being who was in some sense self-made, a product or achievement of its own (caring) synthesis, could be a carer about anything. Since nothing would matter if there was nobody to care (or so it surely seems), the emergence of carers is a momentous moment—or process—in eternity, rather like the emergence of life on earth. Nozick’s concepts of “reflexive caring” and “self-synthesis” are ideas that echo obscure profundities from earlier philosophers (for example, Kant and Sartre), but have the virtue of being developed step-by-step in the broad daylight of Nozick’s analytic philosophy lab.

In the second chapter, Nozick turns to “the question [that] appears impossible to answer”: Why is there something rather than nothing? Most contemporary philosophers wouldn’t go near this question, except to dismiss it brusquely, but Nozick’s treatment of it has a certain weird charm. It’s a tour de force that makes a sort of Mylar purse out of this philosophical sow’s ear, and it permits him to ring some more changes on reflexivity in developing the idea of “self-subsumption.” A self-subsuming principle is one that explains its own truth. For instance: since this very sentence is Gospel, and all Gospel is truth, this sentence is true. Of course, self-explanation can’t amount to self-proof—remember, we have forsaken proofs—but if there were Gospel truths, wouldn’t their being Gospel truths explain why they were true? But can such a tricky idea actually explain why there is something rather than nothing? Could anything else possibly explain this? Can the fact that nothing but a self-subsuming principle explains why there is something rather than nothing itself be the self-subsuming principle that explained this? (Do you feel you have just had your pocket picked?) It is far from clear how seriously Nozick takes the impossible question, and how much he simply wants to use the question as a pretext for the development of the apparently useful idea of self-subsumption, and related ideas. He also uses the question as a pretext for a discussion of mystical experience, and that in turn provides a pretext for his outrageous Sherlock Holmes imitation, as he uses the methods of pure deduction to arrive at a conjecture about the shocking secret of Hatha Yoga. While this chapter’s sheer ingenuity will delight many, it will probably convince as many more—wrongly—that philosophy is just a bunch of intellectual games and tricks after all.

That conviction will be strengthened, alas, by the arduous third chapter on knowledge, in which the  siren call of professional infighting lures Nozick in to battle. Here he makes some fine contributions to the perplexities that currently bemuse epistemologists (thus paying his professional dues), and the upshot is the development of his central concept of tracking, which is exploited throughout the rest of the book. But the ratio of detached formula-mongering to engaged insight-seeking rises sharply.

The fourth chapter, on free will, is in my opinion the most valuable and successful by far. The previous chapter’s analysis of knowledge as a matter of “belief tracking truth” now yields an even more interesting twin: free will is action tracking “bestness.” No summary could do justice to the originality and insight in this major treatment of what is, for many of us, the single most compelling and inescapable philosophical question.

The fifth chapter, on foundations ofethics, strives hard for a completely new slant. It is as densely packed with novel formulations as the earlier chapters, but it ends up seeming quirky and unconvincing. I am far from persuaded that value—all value—is rooted in “degree of organic unity,” but I am impressed by how hard it is to come up with a serious objection to Nozick’s presentation of this view. Is there something in it, or is it a trick with mirrors? The last chapter, on the meaning of life, contains some magnificent passages but lacks the architectural strength of the rest of the book.

Philosophical Explanations is a very personal book, and its interlacing of strengths and weaknesses  reveals the author vividly—which should please Nozick: “It is a puzzle how so many people, including intellectuals and academics, devote enormous energy to work in which nothing of themselves or their important goals shines forth, not even in the way their work is presented. If they were struck down, their children upon growing up and examining their work would never know why they had done it, would never know who it was that did it.” We discover that Nozick is unabashedly addicted to midnight bull session questions, a professorial stand-up comic steeped in the tradition of Woody Allen and Philip Roth, a trickster in spite of himself, a devoted father, and an amazingly quick study, who not only has read omnivorously, but seems to understand it all as a participant, not a spectator. For instance, he can enter the fray in evolutionary biology and, in a footnote, toss off confident asides that make positive contributions to current controversies in that field.

Nozick’s very quickness, however, makes troubles for him on at least two fronts. Philosophically, he  sometimes finds a tricky innovation that seems to him to polish off a problem, and he settles for it too swiftly and moves on. Pedagogically, he overestimates the general reader’s capacity to absorb his high-intensity instruction; one does not need to have mastered recursive function theory or mathematical logic (or Bayesian decision theory or a dozen other such things) in order to understand this guru’s answers, but those of us who haven’t will sometimes find the going hard, and even the reader familiar with the technicalities will on occasion find himself thumbing ahead for the punch line. But the book can’t be skimmed. As Richard Wollheim comments in the preface to his On Art and the Mind, “The lesson, to be learnt only very slowly, is that philosophy has virtually nothing to offer those who would rifle it.”

I have created the impression that Nozick has betrayed his own intention and lapsed into logic-chopping, and that impression needs some correction. Even when he is engrossed in pursuing a logical quarry, he is not blinkered the way so many philosophers are; he has the circumspection and detachment needed to make mid-course corrections, and to comment, for instance, “Only a philosopher would think that this was a clincher” or “And yet, granting all this, there remains the feeling that a switch is being pulled.” He is generous with methodological reflections, which are invariably wise and often startling-for instance his celebration of the virtues of “faking it” on some occasions, and his defense of teaching the history of philosophy with the help of “crude formulations of philosophical  positions.” (The crude, intuitive versions of the great ideas have all the influence, after all, not the  meticulously worked out versions uncovered by scholars.) He also dares to show us the scrambling, behind-the-scenes process of his thought, pointing out the avenues that tempt him but lead him into the fog, candidly admitting perplexity, even giving up on occasion without trying to hide the fact.

This candor will probably annoy some philosophers, but it ought to be particularly appreciated by the  outsiders, especially the students of philosophy, who are usually shown only the armor-plated products—machines left behind by their creators to perform some alien task—and must wonder what it’s like to be a philosopher and whether they could ever be one. It is a shame that Nozick squanders some of this communicative fellowship with simple inconsistencies of exposition that a stern editor, playing ombudsman for the lay reader, could easily have prevented. How, for example, can such a brilliant expositor of difficult concepts let himself refer without explanation to “grue and bleen,” the “paradigm case argument,” the “de re/de dicto” distinction, and “Fregean unsaturated concepts”?

For years I’ve wished I had a contemporary book of philosophy to recommend to intelligent non-philosopher friends, a book I could proudly stand behind and say “This will show you why philosophy is worth doing; this you will understand and appreciate.” Nozick has written that book, for which I am grateful, but unfortunately he has embedded it in a longer and much more difficult book, written, like most philosophy books, for a few professional colleagues.

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