Alfonso

A mathematician of uncertain date, author of a treatise on squaring the circle, extant in a manuscript in the British Museum (additional manuscripts, 26,984). Alfonso claims in the prefatory remarks to have found and demonstrated the possibility of constructing a plane figure, equal—not merely approximately, but exactly—to the area of a given circle. He professes to have put an end to all doubts on the subject, such as were entertained by Aristotle, and controverts the opinions of Ibn Roshd and Ibn Sina, who had declared the demonstration to be impossible.

S. A. H.