The New Gospel

What makes for a beautiful problem in science? … It may be logical beauty: Proof that the set of prime numbers cannot be finite — since the product of any set of prime numbers plus one gives a new prime number — is as aesthetically neat in our times as it was in Euclid’s.  But a problem takes on extra luster if, in addition to its logical elegance, it provides useful knowledge.  The shortest distance between two points on a sphere is the arc of the great circle is an agreeable curiosity; that ships on earth actually follow such paths enhances its interest.