A metaphysical term meaning ‘existence’, employed by philosophically-inclined thinkers such as al-FÄ�rÄ�bÄ« (d. ca. 950), Ibn Rushd (d. 1198), al-SuhrawardÄ« and MullÄ� á¹¢adrÄ� (d. 1050/1640). According to Ibn Sina (d. 1037), God is the wÄ�jib al-wujud (‘the necessary existent’ or ‘the one whose essence is to exist’). Sufis use the term ·É³ÜÂáÅ«»å in different ways. Ibn al-Ê¿ArabÄ« (d. 638/1240) is regarded as the father of the concept of waḥdat al-·É³ÜÂáÅ«»å (the unity of being).