set include BOOL off . in basic-nat.maude in boolean.maude set include BOOL off . fmod NAT+OPS is protecting BOOLEAN . protecting BASIC-NAT . op _*_ : Nat Nat -> Nat . op _-_ : Nat Nat -> Nat . op _<=_ : Nat Nat -> Bool . op _>_ : Nat Nat -> Bool . vars N M : Nat . eq 0 * N = 0 . eq s(M) * N = (M * N) + N . eq 0 - N = 0 . eq s(M) - 0 = s(M) . eq s(M) - s(N) = M - N . eq 0 <= N = true . eq s(M) <= 0 = false . eq s(M) <= s(N) = M <= N . eq M > N = not (M <= N) . endfm red s(s(s(0))) * s(s(0)) > s(s(s(0)) - s(0)) . ***( reduce in NAT+OPS : (s(s(s(0))) * s(s(0))) > s(s(s(0)) - s(0)) . rewrites: 20 in -10ms cpu (0ms real) (~ rewrites/second) result Bool: true ) set include BOOL on .