Let's doodle - using the inquisitive mind of mankind circa 300 B.C. to 15^th century A.D.

 
From the invention of a wheel - and paper - and art, you get the creation of a single circle - and a stright line - and the ability to "play" with any combination of these two - a term formalized as "ruler-and-compass construction".

 

So much can be done just by dividing things in half and joining the points of intersection.
For Example - a hexagon and a pentagon

 
... and what intrigued mankind was this truth
     - these shapes are there regardless of the size of the circles