# Recent Posts

## the Well-Ordering Principle

Here's a nice fact about the natural numbers: Well-Ordering Principle. Every nonempty collection of natural numbers has a least element. Observe, before we prove this,...

## Complete Induction

Induction is like climbing a ladder. But there are other ways to climb besides ladders. Rock climbers don't just stand on one step. To get...

## Mathematical Induction

Many statements in mathematics are true {\em for any natural number}. For example. Fundamental Theorem of Arithmetic. Every natural number has a unique prime decomposition....