According to Ibn Sīnā's epistemic standpoint, essences such as humanity or white cannot be formed by abstraction from perceiving concrete things; since as he argues above, when a specific human being or a white thing is present in the mind or more precisely in memory what is perceived is this individual being Zayd or that white thing. Moreover, how do we come to the general notion of number? For this kind of abstraction or rather extraction is not done in the first experience, at least another experience is needed; it is not a question of time though temporality is involved.