 Kant's synthetic "a priori", then, butressed both physics—at the time, Newtonian—and metaphysics, too, but incidentally discarded scientific realism, the notion that scientific theories are true descriptions of the external world in itself.Kant's transcendental idealism triggered German idealism, including G F W Hegel's absolute idealism.In the French Revolution's aftermath, fearing Western society's ruin again, Auguste Comte was fed up with metaphysics.