Mind mapping is a visual method for rapidly capturing thoughts and relationships. It's a powerful tool for brainstorming and organizing thoughts on the fly.

(DANNY HILLIS:) I have always envied Alexander the Great, because he had Aristotle as a personal tutor. In those days, Aristotle knew pretty much everything there was to know. Even better, Aristotle understood the mind of Alexander. He understood which topics interested Alexander, what Alexander knew and did not know, and what kinds of explanations Alexander preferred. Aristotle had been a student of Plato, and he was himself a great teacher. We know from his writings that he was full of examples, explanations, arguments, and stories. Through Aristotle, Alexander had the knowledge of the world at his command.

Of course no one today knows all that is known, in the sense that Aristotle did. Now there is far too much knowledge for that to be possible. The scientific revolution, and the technological revolution that followed it, led to a self-reinforcing explosion of knowledge. The explosion continues. Today not even the most highly trained scientist, the most scholarly historian, or the most competent engineer can hope to have more than a general overview of what is known. Only specialists understand most of the new discoveries in science, and even the specialists have trouble keeping up.

This problem isn't new. In 1945, Vannevar Bush wrote an essay for Atlantic Monthly about out the problem of too much knowledge. He wrote,

Intertwingularity is not generally acknowledged - people keep pretending they can make things deeply hierarchical, categorizable and sequential when they can't. Everything is deeply intertwingled.
- Ted Nelson

Is it possible to catalogue every human idea? Japan-based researcher Darryl Macer thinks so, and last month he proposed in the journal Nature to count the number of human ideas and map them. This plan, while a clever attention grabber, will not succeed and demonstrates a worrisome mode of thinking.

Macer, an associate professor of biological sciences at the University of Tsukuba in Japan, writes that "although the human mind appears to be infinitely complex ... I would propose that the number of ideas that human beings have is finite, and call for a project to map the ideas of the human mind."