al-burhan al-limi The mode of reasoning which procees from a cause to its effect.

al-burhan al-limi The mode of reasoning which procees from a cause to its effect. As "a proof why a thing is", it starts from the cause or the universal and deduces the effect or the particular from it: the cause here is not merely the efficient cause (al-‘illat al-fa‘iliyah, q.v.) but also the formal cause (al-‘illat al-suriyah, q.v.), i.e. the reason why a thing is; technically also called ta‘lil (q.v.) as opposed to istidlal (q.v.).

al-burhan al-mutlaq Absolute proof or apodictic demonstration of a conclusion in a logical syllogism from propositions or premisses which are certain and self-evident, i.e. such as belong to the category of yaqiniyat (q.v.) al-basa’it al-ustuqussiyah "The elemental simples" , i.e. the four elements: fire, air, water and earth. See also al-arkan al-arb‘ah and ustuqussat.

al-basa’it al-mjarradah "The abstract simples," an expression used by Mulla Sadra (979-1050/1571-1640)[website - Biography] to denote the intelligences and souls of the celestial spheres. See also al-‘uqul al-‘asharah. al-basait al-‘aqli "Conceptually simple", i.e. of which it is impossible to think that it could be divided even mentally, for example a point in geometry.

basar "Sight": it is power placed in the two hollow nerves which meet each other in the brain; thence they separate and go to the two eyeballs. By this power are perceived rays of light, colours, shapes, sizes, motions, the beautiful and the ugly and other things. There are, however, three different theories of vision discussed by the Muslim philosophers.

According to the theory labeled as Platonic theory of vision; a ray of light emanating from the eye falls on the surface of an object, and this enables us to see it. Ibn Sina, however, considers this theory untenable; for were it true we should be able to see things in the dark as we see them in the light. According to the second theory, it is the formative faculty (al-quwwat al-mutasawwirah, q.v.) itself which, so to say, goes out to the object to meet it, and hence we see it.

This theory too is untenable; for were it true we would not be able to distinguish the objects which are absent from those which are present. The third theory, which is called the Aristotelian theory of vision, holds that whenever light falls on an object its shape transmitted through the various transparent media is imprinted on the vitreous humour of the eye, and hence we see it.