FreeMind is a premier free mind-mapping software written in Java. The recent development has turned it into high productivity tool. The operation and navigation of FreeMind is quite fast because of a one-click "fold / unfold" and "follow link" operations.
If you want to write a completely new metaphysics, why don't you use FreeMind? Or do you want to keep personal knowledge base, which is easy to manage? Why don't you try FreeMind? Do you want to prioritize, know where you are, where you've been and where you are heading? Have you tried FreeMind to keep track of all the things that are needed for that?
We use FreeMind for our office project presentation last week.
FreeMind is a convenient and nearly self explaining application. It is fun to sort ideas or develop structures with it. I would like to say it is the best real Open source mind map project