Michael W. Grenke’s “Another Euclid”

Euclid presents the reader with proofs about eyes and what they see.  He gives us proofs about the height of trees and the depth of ditches.  Some of the parts of the proofs are sunlight and shadows and mirrors and chariot wheels.  Euclid offers comments about natural...

Peter Pesic’s “Understanding Understanding”

What does it mean to understand something, especially something one finds really hard  to understand? I take it that “understanding” must necessarily fall far short of “complete understanding,” which seems superhuman. More modestly, what does it mean to make a...