 At the end of his Long Commentary on Book I, Averroes distances himself from Avicenna in so far as the latter maintains that Metaphysics has to prove the composition of matter and form in any body. Averroes claims that only the observation of changes in the substance can explain the existence of these two principles (LC 47H TC83). He is not quoting Avicenna in an exact way, so he may not have had Avicenna’s books of the Shifā’, “The Healing”, at hand. However, he is right in the interpretation, since Avicenna states that the subject matter of natural philosophy is the body as such, not the condition that it is composed of matter and form (Avicenna, Metaphysics, I.2, 7).