On 26-1-2011 19:58, Warp wrote:
>    When talking about logic and the truth value of a statement, one could
> hastily think that true/false is a true dichotomy: A statement is either
> true or false.
>
>    However, this is a false dichotomy. A statement is either true or not
> true (which *is* a true dichotomy), but there are more alternatives to
> 'true' than 'false'.
>
>    For example, "this statement is false" is neither a true statement nor
> a false statement. It's a contradictory one. This is a third option to
> the true/false pair.
>
>    (Note that the above realization is not mine, and I'm not taking any
> kind of credit for it.)
>
>    I was thinking: Are there any other possibilities in logic than true,
> false or self-contradictory?

another is undecidable. For some statements you can prove that you can 
not prove that they are true or false. (indeed see Goedel)

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