Doing Philosophy: From Common Curiosity to Logical Reasoning, by Timothy Williamson (Oxford: Oxford University Press, 2018, ISBN 978-0198822516). 176 pp. Hardcover, $18.95.
Philosophy and philosophers have always had their detractors. In his Devil’s Dictionary, Ambrose Bierce defined philosophy as “a route of many roads leading from nowhere to nothing.” When Bertrand Russell decided to study philosophy, Countess Russell, his grandmother, taunted him with her characterization of philosophical inquiry: “What is matter? Never mind. What is mind? No matter.” The story goes that the first philosopher of the Western tradition, Thales of Miletus, fell into a ditch while looking at the sky, and a witty young woman teased him for having his head so far up in the clouds that he did not know what was at his feet. Thus, the stereotype of the philosopher as distracted and impractical started early.
Many philosophers have themselves expressed deep doubts about the seeming pretensions and oversize ambitions of philosophy. Richard Rorty in Philosophy and the Mirror of Nature (1979) ridiculed the image of philosophy as the “tribunal of pure reason,” with philosophers as the self-appointed arbiters of human rationality. Willard van Orman Quine, one of the leading philosophers of the twentieth century, argued that philosophical epistemology had exhausted its millennia-long effort to provide a definitive foundation for knowledge and a decisive theoretical refutation of skepticism. He proposed that the study of human knowledge should be “naturalized,” that is, taken away from philosophers and turned over to scientists. I have said, only half-jokingly, that philosophy is an academic haven for high-IQ crackpots. Ideologues of every stripe find in philosophy the big words and big ideas that allow them to spend their careers happily grinding axes. Therefore, it is important to ask exactly what philosophy does, how it does it, and what it can and cannot contribute to the instruction of humanity.
Timothy Williamson, Wykeham Professor of Logic at Oxford University, rises to the task in Doing Philosophy: From Common Curiosity to Logical Reasoning. It is difficult to review a book when you agree with practically everything in it. When one philosopher reads another, there are always points of disagreement, of course, but when these are small, belaboring them would only appear nitpicking and captious. I shall therefore indicate what I take to be Williamson’s main claims, indicate why I endorse them, and expand on certain points.
Williamson says, correctly I think, that philosophy, like science, begins with common sense and common curiosity. All animals capable of complex behavior face severe cognitive challenges posed by the environment and their biological needs. Food and water need to be found, mates acquired, and enemies fought or fled. Doing all this requires sophisticated information processing. Commonsense, everyday knowledge allows us to answer questions such as “Where is the water?” or “What is that sound?” Science begins when curiosity drives us to ask broader questions such as “What is water?” or “What is sound?” Similarly, even very young children have a strong sense of what is fair or not, and there are commonsense rules that tell us, for instance, not to show partiality or favor the undeserving. Philosophy begins when we ask questions such as “What is fairness?”
Williamson’s discussion of common sense, science, and philosophy has two important implications. The first is that science and philosophy, while distinct, share many similarities of aim and method. Both arise from common sense and are attempts to answer questions that are prompted by our natural curiosity. Each offers theories to provide systematic and comprehensive answers to our questions, and each seeks to vet those theories as rigorously as possible. Indeed, all theoretical enterprises formulate theories that strive for clarity, coherence, simplicity, comprehensiveness, accuracy, and other such virtues—and practice the stringent assessment of these theories. The advantage that science has over philosophy or history, for instance, is that scientific theories generally admit robust empirical constraint of a quantity or quality not possible in other fields. Yet some questions are so important that even though they cannot be answered scientifically, we seek the most reasonable and plausible answers we can get.
A second implication is that common sense can serve as a check on philosophical theories. This does not mean that philosophical (or scientific) theories can never move beyond common sense, but when a philosophical claim flatly contradicts commonsense beliefs, this raises an intellectual caution flag. For instance, to cite an example given by Williamson, if your philosophical theory of perception implies that we cannot see through glasses, then something seems to have gone wrong. Bishop George Berkeley asserted that matter does not exist and that reality is nothing but minds and their ideas. He realized that this seems to contradict common sense and asked what it means to say that you go to the stable and see a horse. He claimed that all common sense says is that if you go to the stable you will experience the sights, sounds, and smells of a horse, which is consistent with his theory. Berkeley’s critics have replied that when we ordinarily say that we encountered a horse in the stable, we do not mean merely that we experienced horse sights, sounds, and smells. Incompatibility with common sense does not refute Berkeley’s theory, but it might send us back to check his logic for leaks.
Because philosophy cannot test its theories by actual experiment, it relies upon critical discussion and thought experiments. Williamson dedicates chapters to each of these. Philosophers, of course, are disputatious to a fault, and debate—often vigorous and sometimes acrimonious—is the lifeblood of the field. Anyone presenting a paper at a gathering of philosophers can expect to be challenged and that the audience will show little respect for his or her feelings or ego. This may make philosophy appear ruthlessly competitive, but, as Williamson points out, the counterpoint is actually a form of cooperation. Philosophers realize that it takes a village to get at the truth. Philosophers, even—especially—the smartest ones, are prone to overlook assumptions, leap to conclusions, ignore counterexamples, overstate the case, and fall back on rhetoric rather than logic in making a case. Skeptical audiences keep you honest and do not let you get away with laziness, sloppiness, or hand-waving.
A thought experiment is something like this: You park your car in your usual place in the morning. At the end of the day, you think you know where your car is parked, and you find it precisely where you left it. However, unknown to you, just after you parked your car in the morning, thieves broke in and stole it. The theft was observed and reported. The police pursued, and the chase went all around town at high speeds. By a random series of maneuvers, in the attempt to evade the police, the driver returned the car to your original parking space. In such a case, did you really know where your car was parked? You believe it is where you left it, and your belief is true and certainly justified—you have a clear memory of having parked it there. However, can you be said to know where it is parked? Your belief would be true only by the wildest and most unlikely happenstance. Can a belief that is true only “by accident” constitute knowledge?
Thought experiments are fun and an excellent way of testing general claims. Examples such as the above are apparent counterexamples to the classical definition of knowledge as justified, true belief. Such examples appear to show that a belief can meet those criteria but still not constitute knowledge. Such scenarios are known as “Gettier-type counterexamples” after an article published by philosopher Edmund Gettier in 1963, and they have been proven remarkably intractable. By the way, natural science also employs thought experiments. Einstein famously asked what we would see if we rode a beam of light. Galileo confuted the accepted view that heavier objects fall faster than lighter ones by posing a conundrum. What would happen, he asked, if we dropped both a heavier and a lighter object connected by a rope? Would the lighter object retard the fall of the heavier one, or would the whole ensemble, being heavier than each object individually, fall faster than either separately?
To see how theories are compared in philosophy, consider another thought experiment. Philosopher David Chalmers asks us to imagine a zombie—not the brain-munching horror movie staple but a being exactly like you, molecule for molecule. However, unlike you, it has no conscious experience. That is, zombie you says and does everything that you do yet has no thoughts, feelings, desires, pains, pleasures, sensations, or any other experiences. If zombie you is conceivable, Chalmers thinks this shows there is more to consciousness than the physical functioning of the brain. Thus, he contests the view of identity-theory physicalists who hold that each mental event is identical with some physical event.
An identity-theory physicalist therefore has the burden of addressing such purported counterexamples. For instance, the physicalist might note that even if all an individual’s experiences (thinking, feeling, desiring, and so on) are identical with physical processes in that person’s brain, those thoughts, feelings, desires, etc. will not be experienced qua physical. That is, when I perceive red, I will experience it as the quality of redness, not as a flow of energy and chemical interactions between neurons—though in fact that is what it is. This gap between first-person experience and third-person reality means that I can easily imagine the first-person experience without the physical occurrence, or vice versa. I can, like Descartes, imagine consciousness without body or, like Chalmers, imagine body without consciousness. Similarly, though, I can imagine heat as having nothing to do with the mean kinetic energy of molecules, though that is what heat in fact is. Thus, our ability to imagine contrary-to-fact scenarios has no bearing upon what really is identical to what.
Philosophical theories, such as the physicalist identity theory of the mind, therefore rise or fall depending upon their success in addressing alleged counterexamples. This way of vetting theories may seem a poor second-best compared to the assessment of competing scientific theories. Yet as Williamson reminds us, the evaluation of scientific theories also is often complex and roundabout. When a scientific theory makes a prediction that fails to transpire, does this refute the theory? Not necessarily. As philosophers of science have pointed out, no theory is testable in isolation but only in conjunction with several auxiliary hypotheses. Any experimental result depends not just on the theory at issue but on any number of assumptions made about the methods and techniques employed, the equipment used, the lack of interfering factors, and much else. Experimenters must make many “commonsense” assumptions, such as that the experiment will be just as valid if done in the fall rather than the spring or if the experimenter is wearing a blue shirt rather than a white one. If a prediction fails, then something is wrong somewhere, but often it is not evident whether the problem is with the theory itself or some auxiliary hypothesis. The point is that the evaluation of theories in science as well as philosophy often depends upon judgment and interpretation.
One of Williamson’s most interesting chapters is on logic. No tool is more important for philosophers than mathematical or formal logic, with propositional logic and first-order predicate logic as its core. Williamson notes, however, that logic is hardly a neutral arbiter between philosophical theories, because the assumptions of logic can always be challenged. Even the assumptions of classical or standard logic can and have been questioned. For instance, one assumption of standard logic is the principle of non-contradiction: that is, that no proposition is both true and false. However, there are well-known paradoxical expressions that seem to defy this rule. Consider, for instance, “This statement is false.” That sentence is false if it is true and true if it is false.
To deal with such troublesome cases, some philosophers have proposed “dialethism,” the claim that some sentences are both true and false. Williamson says that he is not a dialethist, but he does not regard that view as “crazy.” I think he would endorse the judgment of Quine in his Philosophy of Logic that while the assumptions of standard logic may be coherently challenged, we should follow the “maxim of minimal mutilation.” That is, the deviant logics that challenge the assumptions of classical logic all have side effects that can make the cure worse than the disease. As Quine sees it, the paradoxes that arise in set theory and semantics should be addressed by those fields but not by tampering with the simplicity, clarity, elegance, and usefulness of standard logic.
Philosophy has a relationship with its past that is different from other disciplines. Plato, David Hume, and Immanuel Kant are living presences for philosophy in a way that Isaac Newton, Charles Darwin, and Louis Pasteur, for all their greatness, are not for physics, biology, or medicine. A biologist can go through his or her career without having read On the Origin of Species, but a professional philosopher is expected to have more than a passing acquaintance with Plato’s Republic or Kant’s Critique of Pure Reason. Williamson asks what use philosophy should make of the history of philosophy; that is, what is the relevance of the history of philosophy to the development of philosophical theories today? He notes that past philosophers often did not assume things that are taken for granted today and that reading them can force us to challenge our assumptions. For instance, philosophers today generally assume that moral values outweigh aesthetic ones, but Friedrich Nietzsche held otherwise; reading him makes us confront that assumption. Another advantage of reading the history of philosophy is that it contains magnificent failures that show us what not to do. If very smart people have tried very hard over a long time to carry out a program but fail to do so, this indicates that their efforts probably constitute what philosopher Imre Lakatos called a “degenerating research program.”
Philosophy also has complex relationships to other fields. It employs several mathematical concepts and methods drawn, for instance, from set theory, decision theory, probability, and information theory. Philosophy also partners with other disciplines, sometimes producing hybrid fields. I had the privilege of studying at the University of Pittsburgh’s Department of History and Philosophy of Science, where the reigning assumption is that those who would practice the philosophy of science must be thoroughly familiar with the history of science. Knowledge from other fields also places checks and limits on philosophical theory. As Williamson notes, it discredits a political theory if that theory proposes a system of government that bitter historical experience has shown to be unworkable. (I heard that at the time of the fall of the Berlin Wall, someone scrawled on the crumbling edifice of a dilapidated East German factory, “Workers of the world … I’m sorry.”) Similarly, any metaphysical theory of time cannot ignore the implications of special relativity. I have seen that some philosophers defend their theories of freedom of the will by appealing to our introspective experience of the act of choosing. Yet such arguments must confront the fact that psychological experiments have repeatedly shown how often and how badly introspection leads us astray. The fact that we do not experience our choices as determined does not mean that we know that, in fact, they are not determined.
Williamson concludes by recommending philosophy adopt a model-building methodology of the sort found in many natural sciences. A conceptual model is a simplified but precisely defined simulation of a complex reality. The simplification makes the model comprehensible, and the precision makes it useful. For thousands of years, astronomers have made theoretical models of the solar system. The representation of the planets in these models is, of course, greatly simplified, but their precision makes them extremely useful, for instance, in predicting eclipses. Williamson notes that the use of models goes against the grain for many philosophers, who think that philosophy should seek absolutely general, exceptionless, one-size-fits-all truths. As we saw, the classical definition of knowledge, disputed by the Gettier-type counterexamples, was that knowledge is justified, true belief. Because they make simplifying assumptions, models are not strictly true. Scientific models, for instance, can assume an infinite population, an ideal gas, or a perfect vacuum, though these do not actually exist. Yet the simplicity achieved at the cost of strict truthfulness makes the forbiddingly complex approachable.
Williamson thinks that philosophers who eschew model-building to pursue ever-elusive universal truth are doing their field a disservice. I agree. Traditional epistemologists sought sets of necessary and sufficient conditions for knowledge or justification. Their perennial failure led Quine to recommend that they cease and desist and abandon the field in favor of scientific studies of knowledge. Actually, some philosophers have followed Williamson’s advice and drawn upon neuroscience, computer science, artificial intelligence, and cognitive ethology to develop models of knowledge and mind. Some of these models may prove fruitful and others not, but the model-building approach offers far more promise than the old sterile debates.
Williamson concludes with a brief reflection on the future of philosophy. Philosophy will persist because it arises from the natural human drive to ask certain kinds of questions and insist on rigorous answers to those questions. I think that the immediate future will raise many urgent questions for philosophy. Are we merging with our technology? If so, what does it now mean to be human? Should we wholeheartedly accept such changes or place limits upon them? Artificial intelligence can solve many problems much more effectively than human intelligence. For instance, in seconds an artificial intelligence program can determine who is a good loan risk far more reliably than even the most experienced loan officer. What, then, is intelligence? The future is here, and we need the ancient discipline of philosophy to know where we are and what we should do about it.