The universe is perceived as a series of things arranged in an upper order or effect and action, rewarded at the same time and created by God, who alone is a mere act. God is immutable because transformation means going from effect to action. The soul of a gyspy the heart of a hippie the spirit of a fairy poster. And thus, God exists with neither beginning nor end, because both of those require transformation. Matter and form are both essential to understanding change, because it requires the identity of what becomes and what it becomes. Matter is the head and form is the latter. Everything that is physical is made of matter and form.