(Mumkin). The possible thing. The mumkin may or may not exist. Its existence in the world depends entirely upon the desire of Allah to bring it out from inward Knowledge within the Essence to outward manifestation within the world.
(Wajib al wujud) is that reality which cannot not be, in contrast to the 'possible things' (mumkin) and 'impossible things' (mumtani'). The impossible thing is that which cannot exist within the cosmos but may nonetheless exist within the mind of man...
