The Horror of Münchhausen's Trilemma

A 2,500-year old philosophical problem that lies at the root of our culture war.

The Münchhausen trilemma is “a thought experiment to demonstrate the impossibility of proving any truth… If it is asked how any given proposition is known to be true, proof may be provided. Yet that same question can be asked of the proof, and any subsequent proof. The Münchhausen trilemma is that there are only three options when providing further proof in response to further questioning:

  • A circular argument, in which proof of some proposition is supported only by that proposition;

  • A regressive argument, in which each proof requires a further proof, ad infinitum; or

  • A dogmatic argument, which rests on accepted precepts which are merely asserted rather than defended.”

The Münchhausen trilemma establishes the basis for the three prevailing theories of justification used in contemporary analytic philosophy - coherentism, infinitism, and foundationalism. A theory of justification is, briefly, an explanation of why beliefs can be deemed true.

The first theory, coherentism, is presently much in vogue: It is the theory of justification relied upon by much postmodern thought. Here’s a simple example of coherentist thought: “Donald Trump is a racist.” How do you know he’s a racist? “Because Donald Trump hates black people.” How do you know he hates black people? “Because all racists do.” A more thoughtful coherentist will, of course, weave a much more intricate web, but ultimately all coherentist thought depends upon presenting an unfounded but self-consistent and self-reinforcing set of propositions - popularly called a narrative.

Coherentism lends itself to the partisan divide we are currently experiencing, because each side can support its own propositions self-referentially via its own other propositions. Critics often call America in 2020 a “post-truth” society, but what that really means is a society based on truths justified by rivalrous narratives. (The Leftist narrative is self-consciously coherentist, while the Rightist narrative is actually foundationalist, but is seen by the Left as a competing coherentist narrative.)

The second theory, infinitism, has left most philosophers unsatisfied, and it is not widely supported. Those who call themselves infinitists hold that “the evidential ancestry of a justified belief must be infinite and non-repeating.” In contemporary debate, infinitism is more often mocked than argued, with the famous allegory of William James and the little old lady: “It’s turtles all the way down.” We will set the turtles aside.

The third theory, foundationalism, argues that all propositions fundamentally depend on certain fundamental axioms which are asserted rather than proved. That is, foundationalism holds that certain beliefs can be, and are, justified without reference to other beliefs. Historically, foundationalism has been the core theory of justification used in Western thought for over 2,000 years.

Contemporary right-wing thinking is largely foundationalist, and it is against foundationalism that the postmodernists aimed their weapons. Thinkers such as Richard Rorty, Jacques Derrida, and Donald Davidson assert that “only a belief can be a reason for another belief,” holding that the a proposition is only justifiable in reference to other propositions (e.g. coherentism, as described above). Postmodernists thus deny the validity of foundationalism while upholding coherentism.

The postmodernists were not, of course, the first to launch this assault. The so-called Münchhausen Trilemma is actually Agrippa’s Trilemma, attributed to Agrippa the Skeptic of the Pyrrhonist school of 4th Century BC. Agrippa’s Trilemma phrases the attack a bit differently:

  • Circularity: The truth asserted involves a circularity of proofs.

  • Progress ad infinitum: The truth asserted rests on truths themselves in need of proof, and so on to infinity. 

  • Assumption: The truth is based on an unsupported assumption.

However it is phrased, the Trilemma presents a choice of “three equally unsatisfying options.” Or so it is claimed. Is that the case? Perhaps one of the three options is not “equally unsatisfying” and there are good reasons for adopting one of these three. But before we delve into that, let’s first explain why it matters. It seems a strange thing, after all, to dwell on an unsolved 2,500 year old philosophical dilemma. Why should we care?

Human beings are rational animals; each of us is endowed with our own sense organs and our own mind. By our sense organs we receive precepts about the world, from which we form concepts about what we have perceived. What we perceive and conceive is unique to each of us; no one else has access to the qualia of our senses or the thoughts of our mind. Our consciousness is independent of others.

Human beings are also social animals, who by nature flourish only in society with others of our kind. To exist in society, human beings must cooperate, which requires establishing and asserting their needs and wants, and consensually exchanging value for value with others of their kind. When humans cannot or do not cooperate, they struggle instead, using force or fraud to extract value from others nonconsensually. In both cases, our existence is dependent on others, either as creators, traders, looters, or moochers.

The juxtaposition of our independent rationality and dependent existence creates the necessity for agreement on what can be justified as true. Man in solitude doesn’t need to know or care what others think is true. Man in society must know and care what others think is true: The very concept of exchanging value without fraud presupposes the existence of not-fraud, which is to say, truth.

When human society is simple, the justification necessary to establish truth is equally simple, and typically based on foundationalism relying on sense perception. “Is it rain out?” “Hand feel wet. Yes.” As the complexity of human society increases, the justification necessary to establish truth also becomes more complex. More and more matters arise over which each independent consciousness might disagree. “Does Theodore rightfully own Breckenridge manor?” is no simple question.

As a result, every society of sufficient complexity has created institutions such as courts of laws, trials by jury, assemblies of law, boards of peer review, and other tools to decide what is true. Each such institution fundamentally works the same way: The individual consciousness, with its ability to reason, is embedded within a group of other individuals, and a method used to force the group to come to an agreement (often by deliberation and voting, as in a jury or parliament, but sometimes randomly, esoterically, or even violently).

Over time these institutions, in the process of defining what is true, build a great scaffolding - law, custom, tradition, craft, and practice - that collectively form its culture. But always it remains that what is true about complex matters is reliant on a core set of propositions which are deemed foundational and outside the scope of deliberation. (In the words of America’s founders: “We hold these truths to be self-evident.”)

That is, the culture of every society has historically arisen from a series of agreements made out of necessity to permit cooperation to accept certain propositions as justified, with these agreements developing over time in a hierarchy as society becomes more complex, with all ultimately justified by reference to propositions held by that society as foundational.

But Münchhausen’s Trilemma holds that foundationalism is merely one of three “equally unsatisfying” resolutions to the impossibility of proving any truth. And if there is no possibility of proving any truth, it would seem there is no possibility of justifying the culture of any society as good, beautiful, or right. Worse, those who would argue against our society’s way of life do not even have to grapple with its truth-claims at all: They can simply develop another culture, based on another set of propositions that are self-consistent with themselves, and dismiss our own as irrelevant, unfounded, and wrong.

Historically, most societies have found ways to protect their ways of life from attack. In Antiquity, skepticism was a powerful force; but the philosophers like Pyrrho who explored such matters wrote esoterically for small circles of elites; others, like Plato, explicitly argued for “noble lies” to help preserve the foundations of their society. During the Middle Ages, the new wave of Scholastic philosophers writing in the Classically-inspired Christian tradition were able to rely on Church teaching to provide a foundation that was deemed outside the bounds of philosophical attack. Those who were overly skeptical of the Church could be damned as heretics and burned at the stake.

These salutary circumstances changed with the rise of the Enlightenment. The Enlightenment was the first effort in history to establish a society whose foundational assertions were openly admitted and rationally defended as such. It was a noble effort and much that was good and beautiful came of it. Unfortunately - as Stephen Hicks has shown at book length - the Enlightenment failed in its core effort. The Counter-Enlightenment, which today manifests itself as postmodernism, triumphed; and with the triumph of postmodernism, 21st century Western society became the first civilization in the history of the world to be consciously coherentist in its theory of truth.

Coherentism, being unfounded and circular, inevitably leads to competing justifications of truth which are incomparable and hence irresolvable. Since some method of forming consensus over truth is necessary for a society to allow cooperation without fraud, a society based on rivalrous coherentist theories is not sustainable. And such is the state of affairs we find ourselves in today: Culture war. Partisan mobs shrieking rhetoric to each other, deaf to any reason or argument the other side may offer. Culture war always begins with words. It always ends with swords.

Western society has actually faced a similar situation once before. At the start of the Early Modern period, society’s truths were justified on the foundation of the teachings of the Catholic Church. In 1517, Martin Luther nailed the 95 Theses to his Church door and launched the Protestant Reformation. As documented in The Unintended Reformation, the first or “Magisterial” stage of the Protestant Reformation shook Europe to its very foundations (in the philosophical sense), replacing Church doctrine with the literal Word of God as found in Scripture. Unfortunately, Scripture proved susceptible to multiple interpretations, and soon a second wave (the “Radical Reformation”) arose, replacing the Lutheran and Calvinist interpretations of Scripture with others, more profound in their differences with the Catholic Church.

What happened to Europe as a result? Unmitigated disaster! The Wars of Religion started in 1517 and didn’t end until 130 years later with the cataclysmic Thirty Years’ War (1618-1648). It is common in war for each side to feel justified in fighting, but in the Wars of Religion, each side went to war certain that God was its patron and Satan its enemy. There could be no compromise, no treaty, no rational settlement of the differences of opinion. The Thirty Years War killed one-third of the population of Germany and Sweden - a casualty rate considerably higher than what the Soviet Union endured in World War II!

In the aftermath, Europeans stopped killing each not because they had come to an agreement, but because they agreed to disagree. They had to: They could fight no more. Everyone wanted victory; but victory was impossible, so tolerance would have to do. The virtue of tolerance was that it stopped the bloodshed. The Peace of Westphalia was a treaty of exhaustion.

That the Enlightenment began immediately after the Thirty Years’ War is no coincidence. The early thinkers of the Enlightenment lived through the conflict; they saw what it had done to their society. Thomas Hobbes published Leviathan, the first modern work of political philosophy, in 1651, a mere 3 years after the war. The thinkers of the Enlightenment sought to replace the ruptured Christian culture of Europe with culture founded on secular reason.

The fact that this project has failed, and that we are careening again, towards a state of intellectual war between competing and irreconcilable cultures, should make us quite uneasy.

But what is to be done? Is the Trilemma unanswerable? Is it ultimately impossible to prove anything true? The Trilemma is one of the Vultures that circles us, pinned as we are to the Tree of Woe.