The world is nothing but variety and dissimilarity.

—Montaigne

W hen the Berlin Wall still stood, and Germany was divided, I had trouble remembering which Germany was which. Was the “Federal Republic of Germany” the Communist part, or was that the “German Democratic Republic”? At last I realized the answer: the place that has to call itself democratic isn’t. Now consider: we have one discipline called physics and another called “political science.” Which is the science?

The philosopher Stephen Toulmin, for many years my colleague at Northwestern University, ascribed bogus claims of scientific status not only to a thirst for prestige but also to a mistaken view of knowledge. Since the seventeenth century, philosophers and educated laymen have presumed that true knowledge resembles Euclidian geometry. Newtonian physics, which reduced the amazingly complex motions of the planets to four simple laws, served as a model for all knowledge. And so in the nineteenth century, Auguste Comte, who coined the term “sociology,” originally proposed to call his new discipline “social physics.” In our time, economics downgraded the study of mere historical facts in favor of timeless mathematical models. The humanities as well as the “social sciences” suffer from “physics envy.”

Toulmin spent his career combatting such fallacies, which he found not only philosophically mistaken but also socially destructive. Abstract rationality, he argued, is only one model of knowledge, appropriate in some circumstances but not in others. He once told me about a lecture he attended at the University of Chicago entitled “Is It Rational to be Reasonable?” “I suddenly realized,” he explained, “that the central question of my intellectual life has been the opposite one: is it reasonable to be rational?”

That question shaped Toulmin’s contributions to an impressive variety of disciplines: ethics, rhetoric, social policy, the history of science, and the theory of knowledge. So decisive was his work on rhetorical theory that professors in communication departments are often surprised that his classic study, The Uses of Argument (1958), and the textbook derived from it, An Introduction to Reasoning (1979), represent only a small part of his legacy. He entitled his 1997 Jefferson lecture—which the NEH officially describes as “the highest honor the federal government confers for distinguished intellectual achievement in the humanities”—“A Dissenter’s Life” and chose to devote it to an entirely different field, the role of non-state actors in solving world problems. His last book, The Return to Reason (2001), addresses issues in economic modernization and social policy, while his key contribution to ethical theory, The Abuse of Casuistry: A History of Moral Reasoning (co-authored with Albert R. Jonsen, 1988), reflects his work in medical ethics as a member of the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research. In all of these fields, he reveled in his role as “dissenter” from the prevailing intellectual consensus.

T oulmin and I were initially drawn together by two shared interests. Each of us regarded Tolstoy’s Anna Karenina as our favorite novel, and we twice co-taught a class on it. In addition, as confirmed contrarians, we both deplored recent developments in “critical theory” endorsing absolute relativism. That puerile conclusion was invariably reached by presuming that unless knowledge could be absolutely certain, it was not knowledge at all. Without unshakeable “foundations,” everything was at best a matter of taste but more likely an expression of hegemonic power. As we liked to joke, such reasoning was not only shallow but deeply shallow.

In our view, this post-structuralism was simply dogmatism stood on its head. It leaves no room for reasoned argument, which can thrive only where certainty is not to be had but some positions are better than others. Doctors can offer no guarantees, but we do not therefore conclude that medical treatment is just a matter of taste.

Where there is reasoned argument, there is room for what Toulmin calls “honest and conscientious difference of opinion.” Intellectuals, no less than religious fundamentalists, have a tendency to shut down debate by insisting that only one point of view could possibly be moral. And so I remember the thrill I felt at the opening pages of The Abuse of Casuistry, directed at “the fanatics on both sides” of the abortion debate. “In former times,” the authors observed,

there were always those who could discuss the morality of abortion temperately and with discrimination: acknowledging that here, as in other agonizing human situations, conflicting considerations are involved and that a just, if sometimes painful, balance has to be struck.

As Toulmin was well aware, the very idea of legitimate disagreement about abortion had long been taboo in university circles.

For Toulmin, opinion pertains to some fields by their very nature. One can arrange disciplines along a spectrum, with mathematics at one end, where opinion plays no role at all, and literary criticism at the other. Somewhere in the middle we find clinical medicine, which depends on biological science but cannot be reduced to it.

So many thinkers have presumed that a hard science of human affairs has been or soon will be achieved! When it is, we will simply know things and there will be no more room for reasonable difference of opinion about politics than there is about the Pythagorean theorem. Marxists, of course, have claimed to be “scientific socialists,” and Freudians, insisting on their scientific status, have attributed all contrary opinion to mere “resistance.” “I tell the psychoanalysts to kiss my ass,” the Austrian aphorist Karl Kraus quipped, “and they tell me I have an anal obsession.”

Toulmin liked to quote Aristotle’s Nichomachean Ethics: “it is the mark of an educated person to look for precision in each class of things just so far as the nature of the subject matter admits.” While some fields demand logical proofs, others, like jurisprudence, properly depend on what Aristotle called “rhetoric,” reasoning that strives for nothing more than persuasiveness. Persuasive reasoning, which differs from field to field, is not some sort of inferior logic, but is the right way to approach many questions. Or as Aristotle observes, “it is evidently equally foolish to accept probable reasoning from a mathematician and to demand from a rhetorician scientific proofs.”

Philosophers have usually presumed the opposite, that the rigorous deductive proofs of Euclidian geometry were the gold standard to which all disciplines should strive. To the extent that their reasoning procedures differ from the logical ideal, they are deficient. Toulmin devoted The Uses of Argument (1958) to refuting this philosophical consensus. While some fields do proceed by sheer deduction, and depend on no specific facts about the real world, others, which Toulmin calls “fields of substantial argument,” must operate differently to “achieve whatever cogency or well-foundedness can relevantly be asked for in that field.” By their very nature, they arrive at conclusions that hold only probably, presumptively, and provisionally. To be sure, anyone who maintained that the angles of a triangle total 180 degrees pending future developments would not be making a mathematical error but would not be thinking mathematically at all. But by the same token, medical diagnoses or political reforms can only be provisional.

Toulmin does not maintain that the argumentation of each field has nothing in common with any other, a position leading to the sort of radical relativism he always sought to avoid. While some standards of argument are “field dependent,” others are “field invariant.” One might have thought such a conclusion was mere common sense, but the defense of common sense is, in university settings, a dissenter’s enterprise.

D espite—or because of?—his training in math and physics, Toulmin was sensitive to scientism, the fallacious extension of scientific ideas to social topics. While there is no harm in borrowing scientific metaphors, thinkers often claim scientific status when any scientific context has been left far behind. Today, one need only add the right prefix to the name of a field and one can look down on all those unscientific traditionalists. And so we have neuro-economics, evolutionary aesthetics, and digital humanities. Shall we call this trend the Dawkinsization of the humanities?

Toulmin first studied philosophy under Ludwig Wittgenstein—often considered the greatest philosopher of the twentieth century—who taught that terms have meaning only within a specific set of practices, or “forms of life,” and that we inevitably run into problems when we try to extend them to other areas. Then, as Wittgenstein memorably wrote, “language goes on holiday.” It followed for Toulmin that ideas developed for a specific hard science cannot properly be applied to moral, ethical, and political problems. “Suppose we extend a carefully defined scientific term beyond the range of its theory, and use it in more ambitious but less tangible speculations, then there will be snags at once,” Toulmin cautioned. “There will be no way of checking what is said by experiment or observation and, so, scientifically speaking, nothing to choose between one possible answer and another.” What pretends to be science is really “mythology.” Ripped from the context that gives them meaning, scientific terms resemble isolated pieces of a jigsaw puzzle.

Toulmin loved to cite the intellectuals depicted in Anna Karenina, who make this mistake time and again. In Part VIII of the novel, Tolstoy’s autobiographical hero Konstantin Levin suffers an existential crisis when he realizes, not just theoretically, but to the very depths of his soul, that death renders all human action meaningless. He had long ago exchanged his religious beliefs for scientific ones, but now he grasps that science cannot answer questions of meaning or value. Is it good or bad that a stone falls at 9.8 meters per second per second? Such questions make no sense, and, for much the same reason, no scientific theory can or ever will squeeze meaning from physical law. Levin thinks: “The organism, its decay, the indestructibility of matter, the law of the conservation of energy, evolution . . . were very useful for intellectual purposes,” in connection with their respective disciplines, but utterly worthless for easing Levin’s terror. In turning to science for meaning, Levin “was in the position of a man seeking food in a toy shop or at a gunsmith’s.”

No matter how much his fellow intellectuals deride him, Levin comes to recognize that one is not rejecting science when turning to nonscientific ideas to address questions of meaning. As he lies on his back looking at the sky, he thinks: “Don’t I know that that is infinite space and not a rounded vault? But, however I screw up my eyes and strain my sight, I cannot see it but as round and finite, and in spite of my knowing about infinite space, I am incontestably right when I see a firm blue vault, far more right than when I strain my eyes to see beyond it.” Human questions must be answered in human terms, and the supposedly sophisticated attempt to substitute those of biology or physics rests upon a conceptual confusion.

I n perhaps his best-known book, Wittgenstein’s Vienna (1973), Toulmin and his co-author Allan Janik offer a fundamental reinterpretation of Wittgenstein’s enormously influential Tractatus Logico-Philosophicus, which had shaped the English analytic and positivist philosophical movements. A student of Bertrand Russell, Wittgenstein was praised for developing a bloodless calculus of abstract propositions. To hold this view one had to disregard the concluding portion of the Tractatus, a series of aphorisms about ethics, the meaning of life, and the “mystical.” This conclusion, which seemed to come from nowhere, was dismissed as an irrelevant indulgence of Wittgenstein’s personal idiosyncrasies.

By contrast, Toulmin and Janik contend that the final section of the Tractatus was for its author the very point of the book. Reconstructing the questions preoccupying Wittgenstein long before he met Russell, they situate his thought in the Viennese culture of Mahler, Schönberg, Loos, Hertz, Boltzman, and, above all, Karl Kraus. It was a culture that had rediscovered Schopenhauer and Kierkegaard, and was deeply fascinated with Tolstoy. It could not, in short, have been further from the Cambridge philosophers who banished questions about life’s meaning as vague and primitive.

Tolstoy in particular shaped Wittgenstein’s thought. As a soldier in the Austrian army, Wittgenstein carried copies of Tolstoy’s stories and Gospel in Brief everywhere. His friends jokingly referred to him as “the man with the Gospels.” The end of the Tractatus makes sense the moment one recognizes it as a loose paraphrase of Levin’s meditations in Part VIII of Anna Karenina.

For Wittgenstein, logic and science are indeed powerless to address questions of life’s meaning. “We feel that even if all possible scientific questions be answered, the problems of life have still not been touched at all,” Wittgenstein explains. But that does not mean these problems do not matter. It means that they must be addressed otherwise—for example, by literature.

Like Levin, Wittgenstein reasons that “the sense of life” cannot be a fact in the world, but must lie outside it. It cannot belong to the chain of cause and effect, or anything connected with natural laws, because it must illumine life as a whole. Or as Levin comes to understand: “If goodness has causes, it is not goodness; if it has effects, a reward, it is not goodness either. So goodness lies outside the chain of cause and effect.”

Levin at last realizes that if one lives rightly moment to moment, one can sense life’s meaningfulness, but one will still not be able to express it. What changes for him is not some fact in the world, but the world itself, which, as Wittgenstein paraphrases the point, “must wax and wane as a whole.” Ultimate questions are not answered, but they vanish in the face of meaningfulness and goodness directly experienced. Wittgenstein at his most Tolstoyan explains: “The solution of the problem of life is seen in the vanishing of this problem. (Is not this the reason why men to whom after long doubting the sense of life became clear, could not then say wherein this sense consisted?).” Russell notwithstanding, the genuinely inexpressible is indeed real. We come to know it not by logical deduction but because “it makes itself manifest. That is the mystical.”

When Levin comes to this realization, he understands that meaningfulness has always been there right before his eyes, hidden in plain view. Cloaked in its ordinariness, it is a daily miracle. “And I watched for [material] miracles, complained that I did not see a miracle that would convince me,” Levin thinks. “And here is the miracle, the sole miracle possible, continually existing, surrounding me on all sides, and I never noticed it!”

This sense of meaningfulness in ordinary life constituted, for Tolstoy and Wittgenstein, the essence of religious experience. Religion is not primarily a matter of dogmas, which are really attempts to express that inexpressible essence. They gesture at the “mystical.” That is why different religions do not necessarily contradict each other. Unlike so many intellectuals of his time and since, Wittgenstein took religious experience with the utmost seriousness.

L evin also comes to recognize a truth about ethical reasoning that figures prominently in Toulmin’s thought. Modern philosophy notwithstanding, ethical reasoning does not properly work by deduction from abstract principles or laws. As Aristotle pointed out, such an approach leads to moral monstrosity because “all law is universal but about some things it is impossible to make a universal statement that is correct.” Principles are formulated with a paradigm situation in mind, but life presents complexities and contingencies never dreamed of. At such times, one needs good moral judgment, and judgment by definition is not a matter of rules. Rather, it is acquired by sensitive observation of many particular cases and constant reflection on one’s mistakes. As Tolstoy liked to say, good ethical judgment depends on “moral alertness.”

By training his judgment in this way, Levin gradually learns to make the sort of moral decisions he used to find baffling. He knows he must hire laborers cheaply, and can sell straw to peasants even in time of scarcity, but he cannot make profit from taverns or neglect to lend a peasant money in debt to a loan shark. Tolstoy provides a page of such examples, but never offers the rule that Levin follows, precisely because there is no rule. Levin responds to each set of particularities with an educated sensibility that improves as it is used, case by case. Tolstoy, in short, is recommending the tradition of reasoning called (in the non-pejorative sense) casuistry, reasoning by analogous cases.

Serving on the commission for medical ethics, Toulmin at first wondered how people of different religions, conflicting schools of thought, and a variety of professions could ever come to agreement. Would matters of life and death be decided by a six-to-five vote? In fact, nothing of the sort happened. When presented with particular cases, everyone agreed on what was right and wrong. Had they reasoned down from principles, they could never have come to an understanding.

It was only afterwards that they all justified their conclusions in terms of their prior religious or philosophical commitments. It was as if they had to pretend they used top-down reasoning when in fact they had, quite fortunately, reasoned up from particulars. Wouldn’t they do still better if they could recognize and so refine what they were actually doing? It was this experience with medical ethics that led Toulmin to examine and revive the tradition of casuistry. As with “rhetoric,” he wanted to save the term from opprobrium.

Toulmin discovered that casuistry had been abandoned for much the same reasons that led to the chimera of social science. With the triumph of rationalism, and the ideal of logical deduction from abstract principles, casuistry lost prestige. But it did not entirely disappear. Rather, Toulmin argues, it found a new home in the realist novel.

For what are realist novels but extended case studies? Novels show the overwhelming intricacy of things: contingencies eluding any pattern, idiosyncrasies baffling all psychological theories, and moral subtleties beyond the reach of any ideology. If the hero of a realist novel should embrace a theory as the key to ethics or politics, he is sure to find himself in a situation more complicated than his theory allows. He encounters what might be called the irony of outcomes, and the story of that encounter is the masterplot of ideological novels as different as Turgenev’s Fathers and Children, Dostoevsky’s Crime and Punishment, Conrad’s The Secret Agent, and James’s The Princess Casamassima. They all demonstrate the superiority of a fine discrimination of moral particulars not just to one but to any possible theory. If philosophers teach the simplicity of things, then novelists reveal their irreducible complexity.

W hen cultures take the wrong path, they find it hard to change direction. Often enough, thinkers cannot imagine any alternative because their habits of thought are themselves the product of the chosen path. Of course, had their predecessors taken a different path, the alternative habits of thought that resulted would have proven just as resistant to change. Intellectual egoism predisposes people to believe that their prejudices are validated by History itself. In either case, what might have happened, but did not, remains in the shadows.

Nevertheless, cultures, no less than individuals, sometimes make choices that answer to their current needs but prove counterproductive later on. Then they require a sort of philosophical therapy. They need to become aware of their habits of thoughts and the circumstances that initially generated them. Only then could they go back to explore the road not taken.

Toulmin offers such therapy in Cosmopolis: The Hidden Agenda of Modernity (1990), which constructs a diagnostic history of ideas. Intellectual historians usually trace the modern era to the seventeenth-century rationalists, but Toulmin proposes that “we may . . . need to ask if the modern world and modern culture did not have two distinct origins rather than one single origin,” with the second scientific and philosophical phase “leading many Europeans to turn their back on the first” literary or humanistic phase. The rationalists and dogmatists (Descartes, Leibniz, and Newton) replaced the skeptical humanists (Montaigne, Erasmus, and Shakespeare) as intellectual models. The writers were dismissed as merely literary and their works as little more than philosophy with sugar coating.

Why did European thought change direction? In Toulmin’s account, the religious wars of the seventeenth century, which took the lives of one in four Central Europeans, created an urgent demand for some way, acceptable to all, to resolve problems. What was needed was a Method, which would be neither Catholic nor Protestant, French nor German, contemporary nor traditional. It would depend on nothing merely anthropological or historical. The model, as should now be clear, was Euclidian geometry and the hope was that all fields of inquiry would yield to it. Nothing else would be regarded as true knowledge.

Henceforth all respectable disciplines had to be abstract rather than dependent on particular experience; theory-driven rather than directed to specific practical needs; true everywhere with no debt to any tradition or place; timeless rather than timely; and, above all, categorical rather than subject to exceptions.

Aristotle liked to say that in human affairs judgments could be true only “on the whole and for the most part.” He distinguished between theoretical reasoning (episteme) and practical reasoning (phronesis). To solve current problems, Toulmin called for a revival of phronesis. In Return to Reason, he pointed to the disasters caused when economic modernizers working for third-world countries recommended solutions based on timeless economic principles without regard to local conditions. In much the same spirit, progressive economists, who seem to have learned nothing from the failure of such schemes in Africa, offered post-Soviet Russia no less catastrophic recommendations.

S hakespeare and other sixteenth-century humanists took delight in the sheer diversity of things. In his correspondence with Luther, Erasmus was especially critical of the Protestant reformer’s dogmatic certainty. And Montaigne repeatedly insisted that the complexity and variety of people defeat any significant generalizations. “Man in all things and throughout is but patchwork and motley,” he cautions. “Those who make a practice of comparing human actions are never so perplexed as when they try to see them as a whole. . . . He who would judge them in detail, and distinctly, bit by bit, would more often hit upon the truth.” Toulmin noted that Montaigne, who does not figure in the curriculum of philosophy departments, “came closer than I thought possible to the ideas of my teacher, Ludwig Wittgenstein.”

My own attraction to these ideas derived from a study of Russian literature. By the time I met Toulmin, I had come to regard Russian cultural history as the struggle of the great writers with the “intelligentsia,” a term that in Russia meant not all educated people but those committed to an all-encompassing theory promising to save humanity. An intelligent (member of the intelligentsia) had to be a revolutionist, socialist, and atheist, and he or she had to accept that some scientifically validated theory guaranteed the correctness of political actions—the more all-encompassing, the better. Lenin, Trotsky, and Stalin are simply the best-known intelligents, and totalitarianism, as Dostoevsky predicted, was the outcome.

The great writers set themselves against this whole way of thinking. As one prominent critic observed, “the surest gauge of the greatness of a Russian writer is the extent of his hatred for the intelligentsia.” Keenly aware of what happened when the intelligentsia seized power in 1917, I devoted my energies to studying the counter-tradition of Tolstoy, Dostoevsky, and Chekhov.

I was therefore especially saddened when a mindset similar to that of the Russian intelligentsia took over literature departments themselves. Toulmin’s ideas helped me translate the core insights of literature, and especially Russian literature, into a defense of the humanities from the onslaughts of today’s humanists.