In which logic eats itself
A proposition (the Münchhausen Trilemma) that proves that nothing can be proven:
1. A justification is true only if the means by which that justification is made are also justifiably true. In justifying the means, one must also justify the means of justifying the means, and then it's turtles all the way down.
2. You could stop the endless justification by having a statement justify itself (that is, a circular justification), but that means your justification is no longer valid.
3. You could stop at some 'common sense' level, but then your justification is no longer certain.
Thus, no justification is certain. Even this one.
1. A justification is true only if the means by which that justification is made are also justifiably true. In justifying the means, one must also justify the means of justifying the means, and then it's turtles all the way down.
2. You could stop the endless justification by having a statement justify itself (that is, a circular justification), but that means your justification is no longer valid.
3. You could stop at some 'common sense' level, but then your justification is no longer certain.
Thus, no justification is certain. Even this one.