Two men at a table, each pointing a finger at the other. Between them, an open book that nobody is looking at. The entire "burden of proof" in one image.

"The burden of proof is on you!"

There. The debate is over. My interlocutor has just uttered the magic formula. He can now cross his arms, lean back in his chair, and wait for me to do all the work while he sips his coffee with the satisfied air of someone who believes he's said something profound.

I'll be direct: the "burden of proof," as invoked in 99% of discussions about the existence of God, morality, metaphysics, or any subject that goes beyond the price of tomatoes, does not exist. It is a legal concept torn from its context, transformed into a rhetorical weapon, and systematically used for one thing only: to spare oneself from thinking.

A legal concept gone astray

Let's start by rendering unto Caesar what belongs to Caesar. The burden of proof exists, and it is perfectly legitimate, in one specific context: law.

In court, the prosecution must prove the defendant's guilt. The defendant does not have to prove his innocence. This is the presumption of innocence, and it is a pillar of Western civilization. The reason is simple and pragmatic: it is practically impossible to prove a factual negative ("I did not steal that car"), and the consequence of an unjust conviction is so severe that we structurally prefer to let the guilty go free rather than condemn the innocent.

All of this is sensible. All of this works. In court.

The problem is that philosophy is not a courtroom. Metaphysics is not a trial. The existence of God is not an indictment. And the person who says "God exists" is not a prosecutor who must convince a jury beyond reasonable doubt while the atheist, draped in his presumption of intellectual innocence, has nothing to do but wait.

And yet. That is exactly how the debate is framed, systematically, by those who brandish the "burden of proof." "You claim God exists? Prove it. I'm not claiming anything. I simply don't believe. The burden of proof is on you." And they settle comfortably into their armchair, like a judge waiting to be presented with the case file.

The fraud of "I'm not claiming anything"

Let's dissect this. The atheist (or agnostic, or skeptic, whatever the label) claims to assert nothing. He says: "I don't believe in God. It's an absence of belief, not a belief. It's a non-position. Degree zero. The empty box. I therefore have nothing to prove."

This is false, and it's false for a very simple reason: the moment you enter a philosophical discussion, you have a position. Even the refusal of a position is a position. Even "I don't know" is a claim ("I know that I don't know," which is a claim about the state of your knowledge and, implicitly, about the difficulty or undecidability of the question). And every position entails premises that must be justified.

The atheist who says "there is no reason to believe in God" is asserting something enormous. He is asserting that he has examined the available reasons and found them insufficient. Has he read the Five Ways? Does he understand the argument from contingency? Can he explain why the classical teleological argument (not fine-tuning, the Aristotelian argument) fails? In the vast majority of cases, the answer is no, no, and no. He hasn't examined the reasons. He decided a priori that they didn't exist, which is exactly the opposite of the neutrality he claims.

And the agnostic who says "the question is undecidable" is asserting something even more enormous: he is asserting that the arguments for and against are of exactly equal strength, or that the question is by nature inaccessible to reason. This is a massive metaphysical thesis, and it needs to be proven, every bit as much as theism or atheism.

The "non-position" doesn't exist. It has never existed. It cannot exist, because the question of God's existence is a question that everyone answers, if only by living. Your life is organized as if God exists, or it isn't. There is no third option. The agnostic lives like an atheist and prays like a theist, which is to say he does neither and calls it prudence.

How a real discussion works

Let's forget the burden of proof for a moment. Let's ask: how does a serious philosophical discussion work? Not a TV panel debate. Not an exchange of slogans on Reddit. A real discussion, between two people searching for truth.

Here's how: you start by agreeing on the premises.

This is the method of all classical philosophy, from Aristotle to Thomas Aquinas through Plato. Before discussing anything, you establish common ground. What do we both accept? What principles do we share? The principle of non-contradiction? The principle of causality? The existence of the external world? The reliability of reason? Good. Let's start there and see where the reasoning leads.

This is exactly what Thomas does in the Summa Contra Gentiles. He explicitly distinguishes between discussions with those who share the premises of faith (where one may invoke Revelation) and discussions with those who don't (where one can only start from natural reason and the premises the adversary accepts). It is a methodological rigor that the burden-of-proof brandishers will never achieve, because they aren't even aware that there is a method.

Within this structure, the "burden of proof" is meaningless. Both interlocutors have the same obligation: to justify their claims from the common premises. If I say "every contingent being requires a cause" and you accept this premise, we can proceed. If you deny it, it's up to you to tell me why, because it's your denial that's at stake. The burden is not on one or the other. It is shared. It rests on whoever advances a proposition.

The imaginary asymmetry

But then, why this tenacious idea that the burden of proof rests on the theist and not on the atheist? Because there is a hidden presupposition, and it is vicious: the idea that atheism is the default position.

I already eviscerated this presupposition in my post on ECREE¹, but it deserves a repeat offence. Atheism is not a default position. Materialism is not the "degree zero" of metaphysics. Absence of belief in God is not the "natural" state of the human mind (the entire history of humanity proves the opposite). And the burden of proof does not rest exclusively on the one who "affirms" as opposed to the one who "denies," because denial is itself an affirmation.

"God doesn't exist" is a claim. "There is no reason to believe in God" is a claim. "The question is undecidable" is a claim. "Atheism is the default position" is a claim. And all of these claims must be justified with the same rigor as "God exists." This is the fundamental symmetry of every honest discussion, and it is precisely this symmetry that the burden-of-proof slogan seeks to destroy.

Why destroy it? Because symmetry is uncomfortable. If the atheist must also justify his position, he can no longer sit in his armchair. He has to work. He has to read. He has to think. And the burden-of-proof slogan is precisely designed to avoid all of that: it transforms the refusal to think into an epistemological principle.

And it works the other way too

Let this be crystal clear: what I just said applies exactly the same way to theists.

The theist who says "you can't prove God doesn't exist, so the burden of proof is on you" is every bit as lazy, every bit as dishonest, and every bit as insufferable as the atheist who does the same thing in reverse. It's the same sleight of hand, performed with a crucifix instead of a microscope.

I know them, these theists who brandish the burden of proof as a shield. "Prove to me that God doesn't exist!" With the same satisfied air. The same laziness. The same refusal to do the work. As if the Catholic faith hadn't had two thousand years of intellectual tradition precisely designed to give reasons. As if Thomas Aquinas hadn't written thousands of pages to demonstrate what he believed. As if the First Vatican Council hadn't solemnly defined that the existence of God is accessible to natural reason.

The theist who refuses to justify his position is, from the standpoint of Catholic tradition, worse than the atheist who refuses to justify his. Because the atheist, at least, doesn't claim to belong to a tradition that demands intellectual rigor. The lazy theist betrays his own. He betrays Augustine, who wrote the City of God to answer pagan objections. He betrays Thomas, who always began with the arguments against his own position. He betrays Newman, who spent his life demonstrating that faith and reason are allies. And he makes Catholicism exactly what its adversaries accuse it of being: an irrational sentimentalism for people who don't want to think.

If you're a theist and your best argument is "prove me wrong," you don't have an apologetics problem. You have a laziness problem. Open the Summa. Read Feser. Work through your Five Ways. And the next time an atheist asks you a question, answer him with an argument, not with a volley return.

The burden of proof is on nobody because it is on everybody. That's the symmetry. And it doesn't do favors.

Hitchens's razor and other tools of laziness

One often hears, in the same breath, "Hitchens's razor": "What can be asserted without evidence can also be dismissed without evidence." It's elegant. It's punchy. And it is of a remarkable philosophical stupidity.

First, because nothing is "asserted without evidence." As I showed in my old post on the notion of proof², the simple fact that a position is defended by someone is, in the Bayesian sense, a form of evidence (it is more probable that a proposition is true if someone defends it than if nobody does). This doesn't mean that every defended position is true, obviously. It means that "without evidence" is a fantasy: there is always something. The question is never "is there evidence?" but "is the evidence sufficient?" And that question, Hitchens's razor doesn't even ask.

Second, because Hitchens's razor refutes itself instantly. "What can be asserted without evidence can be dismissed without evidence" is itself asserted without evidence. It is a philosophical principle that Hitchens never demonstrated, because it cannot be demonstrated: it's a presupposition, an axiom, an epistemological act of faith. By its own criteria, it must be dismissed. Argumentative aikido, once again³.

And third, because applied seriously, Hitchens's razor destroys the entirety of human knowledge. No axiom of mathematics is "proven" (that's the meaning of the word "axiom"). No first principle of logic is "proven" (the principle of non-contradiction is not demonstrable, it is presupposed by every demonstration). Hitchens's razor, rigorously applied, compels us to reject logic, mathematics, and reason itself. Which, you'll agree, is a somewhat embarrassing result for a tool supposedly defending rationality.

The real question

Let's stop talking about the burden of proof. It's a smokescreen. Let's ask instead the only question that matters:

Are you willing to follow the argument wherever it leads?

This is Socrates's question. This is Thomas Aquinas's question. This is the only question that distinguishes a real discussion from a rhetorical match. And it is addressed to both parties, symmetrically, without exception.

If you are a theist, are you willing to seriously examine the strongest objections against your position? Are you willing to understand, truly understand, why an intelligent person can not believe in God? Are you willing to abandon your position if the argument requires it? (Thomas was willing. He always began with the objections. You are not better than Thomas.)

If you are an atheist, are you willing to seriously examine the classical arguments for the existence of God, not the Reddit caricatures, but the real ones, those of Aristotle, Thomas, Leibniz? Are you willing to understand, truly understand, why an intelligent person can believe in God? Are you willing to abandon your position if the argument requires it?

If the answer is yes on both sides, the burden of proof is irrelevant, because both parties are doing the work. And if the answer is no on one side, that side has no business in the discussion, whether theist or atheist.

What remains when you remove the slogan

When you remove the burden-of-proof slogan, what remains? The real philosophical work remains. And it is simple to describe, even if it is difficult to do:

1. Establish the common premises. What do we both accept? The reliability of reason? The principle of non-contradiction? The principle of causality? The existence of an external world? Let's start there.

2. Reason from those premises. Don't invoke authorities. Don't brandish slogans. Reason. Step by step. Proposition by proposition. With the patience of someone seeking truth, not victory.

3. Accept the result. If the reasoning leads somewhere, go there. Even if it's uncomfortable. Even if it calls into question everything you believed. The price of truth is sometimes the destruction of your certainties. It is a price that great minds have always been willing to pay.

This is Aristotle's method. This is Thomas's method. This is the method of every philosophy worthy of the name. And notice that at no point, in this method, does the phrase "burden of proof" appear. Because it has no business there.

The final word

The next time someone tells you "the burden of proof is on you," answer them this:

"No. The burden of thought is on both of us. Let's sit down, agree on our premises, and reason. If you don't want to reason, don't talk to me about the burden of proof. Tell me about your laziness, and we'll save time."

A good-faith discussion begins when two interlocutors agree on the basic premises and prerequisites. Everything else is noise. And the "burden of proof," invoked as a shield by someone who refuses to work, is the noisiest noise of all.

When you say "the burden of proof is on you, not on me," what you're really saying is: "I refuse to do half the work, but I still want to have an opinion on the result." In any other domain, we call that dishonesty. In armchair philosophy, we call it epistemology.

Shutting up would be more honest. And infinitely more productive.