Socratic Paradox

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These two paradoxes are attributed to Socrates:

Paradox 1

I know nothing at all.

In which case, how does Socrates know that he knows nothing?


If he knows that he knows nothing, then it is false that he knows nothing, because there's (at least) one fact he has knowledge of: his lack of knowledge.

Hence I know nothing at all must always be false, whoever utters it.

Paradox 2

Is the following statement in italics true or false?

This statement in italics is false.

Suppose the statement in italics is true.

Then it is false.

That is, what it says is different from the way things actually are.

So, the sentence is not false.

Therefore it is true.

But it cannot be both.


The sentence is meaningless.

Source of Name

This entry was named for Socrates.