## Euclid on Prime Numbers

In Book VII of his Elements EuclidÂ sets forth the following: Any composite number is measured by some prime number. Elements, Book VII, Pr.31 By appealing to the impossibility of an infinite regress of natural numbers, his demonstration takes the form of a reductio ad absurdum. (For the proposition, scroll to the bottom of this post) … Continue reading Euclid on Prime Numbers