Interpretatio B2

Alhacen on the Principles of Reflection: A Critical Edition, with English Translation and Commentary, of Books 4 and 5 of Alhacen’s De aspectibus


In books 4 and 5 of the De aspectibus Alhacen undertakes an analysis of the principles of reflection that culminates with his approach to ‘Alhazen’s Problem’ in book 5:  to find the point or points of reflection in a convex or concave spherical mirror for any randomly posed point of radiation and center of sight.  In the process, Alhacen attempts to establish the basic principles of reflection—e.g., that reflection occurs at equal angles within a single plane perpendicular to the reflecting surface, etc.—on the basis of various controlled experiments.


Books 4–5 in 2 volumes 
Pp. cxxviii + 699

Interpretatio: Sources and Studies in the History of Science B2

Purchase Options

To purchase the printed version of Alhacen on the Principles of Reflection, please send a request by email to or visit online either the American Philosophical Society or the APS fulfillment service, Diane Publishing.



Date Mounted: 

Sunday, January 1, 2012




Item Number: 


Archival Resource Key (ARK):