Loveland, D.

A machine program for theorem-proving


Some success was obtained by causing the machine to systematically eliminate the redundancy; but the problem of total length increasing rapidly still remained when more complicated problems were attempted. The conversion to a quantifier-free matrix in conjunctive normal form requires, of course, a certain amount of pencil work on the formula, which could have been done by the computer. In some cases, whether or not the program could actually prove the validity of a given formula (without running out of fast access storage) depended on how one shuffled the punched-data deck before reading it into the assembler! However, the program performed as well as expected on the simple predicate calculus formulas offered as fare for a previous proof procedure program.