Now it is established in the sciences that no knowledge is acquired save through the study of its causes and beginnings, if it has had causes and beginnings; nor completed except by knowledge of its accidents and accompanying essentials.

— Avicenna, On Medicine (1020)

Source: http://www.fordham.edu/halsall/source/1020Avicenna-Medicine.html

From Avicenna's On Medicine (c. 1020).

Topics: learning