Ibn Khaldun, 1332-1406. Arab historian.

Geometry enlightens the intellect and sets one's mind right. All its proofs are very clear and orderly. It is hardly possible for errors to enter into geometrical reasoning, because it is well arranged and orderly. Thus, the mind that constantly applies itself to geometry is not likely to fall into error. In this convenient way, the person who knows geometry acquires intelligence.

"Geometry enlightens the intellect and sets one's mind right."

Ibn Khaldun (May 27, 1332 AD/732 AH – March 19, 1406 AD/808 AH) was a North African polymath — an astronomer, economist, historian, Islamic scholar, Islamic theologian, hafiz, jurist, lawyer, mathematician, military strategist, nutritionist, philosopher, social scientist and statesman—born in North Africa in present-day Tunisia.