Gurāb is a universal body (kullī jism). (Istilāḥ, 537)
The fact that it is deprived of perception and light is an allusion to its being very distant from the station of aḥadiyya (ahadiyyet, the station of divine oneness) and the sacred realm. Thus, the universal body is metaphorically called gurāb (crow). For it too (like the crow) is distant, and its color is black (the color of darkness). (Kāshānī, 167; Jāmiʿ, 91)