This is a circle.


   Circles come in many different shapes and sizes. They're used in many walks of life, everything from mathematics to gardening. Squares and circles are enemies.


   Some squares are former circles who have grown corners and been expelled from the land where circles live. Circles live in a land of unspoilt natural beauty, where litters of baby circles play happily amongst the wildflowers in meadows.


   A circle dies when it's broken, and then it becomes a line. Some lines will keep moving forever, going wherever they want to go. Other lines can be trained to restrain themselves, and they can serve important functions on tennis courts or on medical forms.
   One day when I was minding my own business, leaning against a lone gunman as I read the paper, a line approached me and asked me for directions to the bus station. I gave it directions, but as I watched it leave I saw that it was going the wrong way. I followed the line into the park, and I caught up with it when it stopped to watch two mathematicians who were about to engage in mathematics. Their names were Eric and Michael. They were putting on their crash helmets when I arrived. There are more accidents and fatalities in mathematics than there are in Formula One.
   The line was trying to attract the attention of the mathematicians in the hope that they'd find a use for it, but they showed no interest in the line.
   I was distracted by the mathematicians testing each other's helmets before they got to work. I didn't notice that the line was being chased by a dog, and it was getting all tangled up. When I saw what was going on, I chased the dog away, but by then the line had become badly knotted and tangled.
   Eric took pity on the line. We took it back to his house and we gave it a bath. We were able to remove most of the knots and the tangles. Eric decided to keep the line. It gets on well with his other lines, and he's been teaching it how to do tricks. The last time I visited his house he showed me how the line would become a curve on his command.
   His new pet has also turned out to be an excellent guard line. It moves quickly around the feet of thieves, making them feel dizzy, and most of them leave. Eric gets three times as many thieves as an average house because no one ever breaks into the houses on either side. The house on the right is full of Rottweilers, and the one on the left is owned by a woman who makes her own dolls. All of these dolls have concealed weapons. They stop smiling at you as soon as your back is turned. Sometimes you'll see their evil glare just as you're turning away. Thieves break into Eric's house rather than taking their chances with the dolls or the Rottweilers.