A school of thought is simply the set of theories and assumptions that an individual psion operates under. Because there are a variety of functional theories on what psionics is, and how it works, it can often be important to understand where a specific individual is coming from when they are explaining a psi function. By organizing documents according to schools of thought, we can better understand how these methods come together, and also understand where they differ, and easily compare them to one another. In some cases, one school of thought will derive from another...being very similar, but not exactly the same. This is often the case when a student who is training under a mentor reaches the point where they begin teaching on their own. A school of thought is considered derivitive when the majority of the methods and theories used in it match that of its progenitor.