The Logic package uses a two-valued logic system, while standard Maple logic is three-valued.  For this reason, all Boolean expressions used in the Logic package must be expressed in terms of the operators &and, &iff, &implies, &nand, &nor, &not, &or, and &xor.

You may either enter expressions in terms of these operators directly into Maple, or transform expressions of type logical into expressions in terms of these operators with the Logic[Import] command.

Note that the Logic package operators do not have the same precedence as corresponding three-valued operators.  In particular, all operators have the same precedence, so  is equivalent to , not . Parentheses should be used to correctly specify the precedence.