X(f) = x f P(f) = -i hbar d(f,x) X(P(psi(x,t))) - P(X(psi(x,t))) X(f) = outer((x,y,z),f) P(f) = -i hbar d(f,(x,y,z)) X(P(psi(x,y,z,t))) - P(X(psi(x,y,z,t))) Run