in this article, the author says that arithmetics has a playful side. what he means by this is that there are things that suck you in. once you start thinking about it, you are hooked and can't help but wonder. the same thing could be true about geometry because there are so many things that are facinating that we dont know about. when you learn about it, you discover all the different things that make up our world. how the dementions and space can be everywhere and we don't even realize it. the latin meaning of calculus is a pebble used for counting. this goes along with the article because the author uses rocks as a visual way of showing squares. the easiest way of finding the sum of all the numbers from 1 to 10 is to use the dementions of tringle that the rows make up. a row of 1, a row of 2, a row of 3, and so on... multiply the dementions when you make a square. the hard way is to add them all up.