It's based on science, specifically a very opinionated version of it.
Hubbard was a genius and I can still hear his laughter echoing from a very expensive grave.
Science (from Latin scientia, meaning "knowledge") is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.http://en.wikipedia.org/wiki/Science
Pseudoscience is a claim, belief, or practice which is presented as scientific, but does not adhere to a valid scientific method, lacks supporting evidence or plausibility, cannot be reliably tested, or otherwise lacks scientific status.[http://en.wikipedia.org/wiki/Pseudoscience