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83. Moore's Paradox

The absurdity of sincere self-contradiction

Try Saying These Sentences

"It's raining, but I don't believe it is."

ABSURD (but not contradictory!)

Part 1

"It's raining"

Claim about the world

Part 2

"I don't believe it"

Claim about my mind

The Puzzle

Each part could be true separately. From a third-person view, someone could be in a state where it IS raining and they DON'T believe it. But when YOU say it about YOURSELF in the present tense... it becomes impossible to utter sincerely. Why?

The Paradox

G.E. Moore noticed something peculiar about sentences like "It's raining, but I don't believe it is." These sentences are:

Not logically contradictory: Both parts can be true (you can be wrong about your beliefs)
Impossible to assert sincerely: Saying it defeats the purpose of saying it

The paradox lies in the gap between what a sentence means and what saying it does. The sentence isn't nonsense—but asserting it is.

Wittgenstein's Assessment

"This is Moore's most important contribution to philosophy."

The Two Forms

Omissive Form

Asserting P while denying you believe P:

"The bank closes at 5, but I don't believe it does."

You're claiming something while explicitly disclaiming belief in it.

Commissive Form

Asserting P while claiming to believe not-P:

"The earth is round, but I believe it's flat."

You're claiming something while stating you believe the opposite.

Why It's Not a Contradiction

Consider: "It's raining, but John doesn't believe it is." This is perfectly sensible! John can be wrong about whether it's raining. The third-person version describes a possible state of affairs.

And in the past tense: "It was raining, but I didn't believe it was." Also fine! Past-me could have been mistaken about the weather.

The problem arises specifically with:

First person: "I"
Present tense: "is/am"
Sincere assertion: Actually meaning what you say

Something about this particular combination makes the sentence impossible to utter sincerely—even though it describes a logically possible situation.

Proposed Explanations

Moore's Own Answer: Pragmatic Norms

Assertion carries an implicit commitment. When you say "P," you implicitly claim "I believe P." Moore's sentences violate this norm—you're undermining your own speech act while performing it.

Wittgenstein's Answer: Hidden Contradiction

In first-person present tense, "P" and "I believe P" become equivalent. "It's raining" just is a way of saying "I believe it's raining." So the Moorean sentence really is contradictory after all.

Epistemic Norms Answer

Beliefs are normatively constrained—they ought to aim at truth and avoid self-falsification. Moore's sentences describe beliefs that violate these norms, making them rationally defective even if logically possible.

"There is currently not any generally accepted explanation of Moore's paradox in the philosophical literature."

— Stanford Encyclopedia of Philosophy

Implications

Moore's Paradox illuminates deep questions about:

Self-knowledge: We have special access to our own beliefs
Assertion: Saying something involves committing to it
First-person authority: "I believe P" isn't just a report about my mental state
Rationality: Some beliefs are irrational even if their contents are consistent

The paradox reveals something peculiar about the first-person perspective—about what it means to be a believer speaking about one's own beliefs. When you say something, you're not just describing the world; you're putting yourself forward as someone who believes it.