Solipsism

http://en.wikipedia.org/wiki/Solipsism

Solipsism is also commonly understood to encompass the metaphysical belief that only one's self exists, and that "existence" just means being a part of one's own mental states — all objects, people, etc, that one experiences are merely parts of one's own mind.

1. Nothing exists
2. Even if something exists, nothing can be known about it, and
3. Even if something could be known about it, knowledge about it can't be communicated to others