The meaning of “circle”

This is my contribution to the week of code.

One of the things I remember from reading Papert (Mindstorms I think) was his explanation of different ways of understanding. He claimed that computation offered a different way of understanding. One example which I think was from the same source concerned the understanding of circle. The demo goes something like this.

Most of probably remember the definition of circle – a closed plane figure consisting of all points equidistant from a point. The ability to produce this definition does not really mean we understand it. He proposed the following demonstration (I hope I am remembering the source appropriately). You can turn this definition into a program (logo).

This demo was generated in Blockly. If you follow the code, you should be see how the code expresses the definition.