In order to talk about chaos and its influence on science and society, we need to have some idea about what it is. This set of presentations is designed to give you that idea.

The above definition has been painstakingly developed over many years. There are, of course, many alternative definitions. One is that a chaotic system has the following properties:

1) It is not equilibrium.

2) It is not a steady state.

3) It is not a transient.

4) It is not periodic.

5) It is not quasi-periodic.

This is reminiscent of the definition of a boomerang: "Pick up an object and throw it. If it does not return, it is not a boomerang."

Humorous as it may seem, there is utility in this definition. The following discussion of the behavior of the logistic equation will help you see why.