Re: A missing definition in "Gödel's Proof" by Nagel & Newman (open letter)

On Nov 2, 4:03 pm, G. Frege <nomail@invalid> wrote:
Wittgenstein also introduced truth tables in his
Tractatus.

Frege, Peirce, and Schroeder hold priority to the concept of truth
functionals (late 1800's). Post and Lukasiewicz first used the tabular
form of turth tables. Wittgenstein is responsible for popularizing the
truth table, and I suspect only for philosophers. Where the electrical
engineers got it, I don't know (and I don't think it was
Wittgenstein).

(Of course the method described in 6.1203 is impractical in
general.)

Currently, for all known decision methods for propositional calculus,
it is not known if any are not impractical (infeasible, exponential
time) on all inputs of a given size.

Mitch

.

Relevant Pages