 His idea of science can be defined as obtaining concepts from meanings and producing them in his mind, as opposite to memorization. Learning by heart all the terms would never be a science and Avempace adds that understanding “everything written in a book” implies understanding the meanings of the terms contained in it. The ability to discern (mayz) the signs of the terms is the key condition to learn any theoretical art. Although the ability exists in most people, the vast majority stifle it from a very young age and Avempace blames this behavior as the main cause for the ignorance, and not the natural lack of ability to discern.