Baron Munchausen

“At the core of all well-founded belief lies belief that is unfounded.”

- Ludwig Wittgenstein, On Certainty

We all hold beliefs that we assert to be true, and we often engage in lively debates about a wide array of topics—sports, politics, religion, diets, and countless others. A glance at the history of human conflict reveals a continuous stream of disagreements, both large and small.

In epistemology, there exists the concept of ultimate justification. Ultimate justification refers to the unquestionable foundation for a belief or knowledge claim. Humans argue as if we possess this ultimate justification ourselves, while treating others as if they lack it.

But what if we could identify ultimate justification for our beliefs? Wouldn’t that enable us to resolve most disagreements? With clear logic underpinning the correct beliefs and assuming open, clear communication, we might be able to set aside our differences and reach consensus.

Unfortunately, achieving this clarity is remarkably challenging.

The Trilemma and Ultimate Justification

The Muncausen Trilemma (also known as Agrippa’s Trilemma or the Agrippan Trilemma) explores the challenge of ultimate justification. When we seek ultimate justification, we find ourselves confronted with three options, none of which fully resolve the issue.

Munchausen Trilemma Model

A visual representation of the three logical structures we encounter in the trilemma. From left to right they are: “infinite regress”, “circular reasoning" and “axiomatic arguments”.

Option 1: Infinite Regress

Munchausen Trilemma Infinite Regress

The logical structure of infinite regress.

The first path leads to infinite regress. We begin with A, which is justified by B. But what justifies B? That would be C. And what justifies C? You can see where this is going. This chain continues indefinitely, leaving us with an endless backward journey that perpetually justifies the next belief without ever establishing a solid foundation.

The beliefs in epistemology that adhere to this perspective are known as “Infinitism”, where infinite regress is accepted and a necessary form knowledge.

Option 2: Circular Reasoning

Munchausen Trilemma Circular Reasoning

The logical structure of circular reasoning.

The second path involves circular logic or reasoning. Here, we again start with A, which is justified by B, but crucially, B is justified by A. This form of reasoning might establish a kind of foundational truth, yet it often falls short for many. It is imbedded in the following statement, “I’m trustworthy because I say I am trustworthy.”

  • A = I’m trustworthy
  • B = I say I am trustworthy

In this case, A is deemed true based on B, while B’s truth hinges on A. However, no rational person would accept this reasoning when evaluating someone’s trustworthiness.

The set of beliefs in epistemology that adhere to circular reasoning are known as “Coherentism”, where a web of circular justification is accepted as knowledge.

Option 3: Axiomatic Arguments

Munchausen Trilemma Axiomatic Arguments

The logical structure of axiomatic arguments.

The third path involves selecting an axiom or a self-evident truth that does not require justification. Unfortunately, this approach can lead others to perceive you as dogmatic. Consider an atheist questioning a Christian about the basis for morality, only to hear, “Because God says so.” In this overly simplified hypothetical, God’s word serves as the axiom, and no further justification is provided.

The constelation of beliefs in epistemology that consider axiomatic arguments to be a form of knowledge are known as “Foundationalism”.

I hear the phrase “the science says,” often used to justify beliefs. What I find particularly interesting is this assertion functions similarly to an axiomatic argument within the trilemma. Although there is always room for critique of scientific studies - such as issues in experimental design or sample biases — they are frequently presented as absolute truths.

Lastly, when René Descartes articulated “cogito, ergo sum” (I think, therefore I am), he aimed to establish an axiom to underpin a structure of knowledge. He had chosedn the third path of the trilemma and was searching for the most reliable axiom to build his knowledge of the world.

The Implications of the Trilemma

Faced with these three unsatisfactory choices, what are we to do in our quest for ultimate justification? The first key takeaway is that there are no fully irrefutable, 100% true, logical structures for our claims. Few, if any, assertions made by humans can be deemed completely true.

Second, it’s more effective to view knowledge or truth as gradations or probabilities of being true (see Bayesian Epistemology). Rather than stating “X is a fact,” we should express it as “I am 95% confident that X is true.” Reality is infinitely complex, and models that simplify it into black-and-white categories often lack the necessary precision.

In light of the uncertainty presented by the Munchausen Trilemma, I leave you with this quote:

“The demand for certainty is one which is natural to man but is nevertheless an intellectual vice. So long as men are not trained to withhold judgment in the absence of evidence, they will be led astray by cocksure prophets, and it is likely that their leaders will be either ignorant fanatics or dishonest charlatans. To endure uncertainty is difficult, but so are most of the other virtues.

Most of the greatest evils that man has inflicted upon man have come through people feeling quite certain about something which, in fact, is false.”

- Bertrand Russell, Unpopular Essays

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