Avicenna, Kitāb al-Shifā ͗; al-Mantiq, Kitāb al-Burhān (ed. A. Afifi, Cairo: 1965) III.4, 214-215:
Among ignorance (al-jahl), there’s that which is simple (basīṭ), which is merely the absence of knowledge ( ͑adam al- ͑ilm) in the soul. […]. And among ignorance, there’s that which is composite (murakkab), and it is not merely an absence; rather, there’s in it, together with the absence of knowledge, the existence of an opinion that is contrary (muḍād) to it, and it is ignorance by way of possession (qunya) and habit (malaka). […]. And this is only called ‘compound’ ignorance because there’s in it a conflict (khilāf) [with] knowledge and an opposition to it in two respects: the first is that the soul is devoid of knowledge, and the second is that, with its emptiness of knowledge, there has occurred in it the contrary (ḍidd) of knowledge.