Experiential philosophy: Metaphysics and altered states of consciousness

This dissertation presents evidence that a number of the great traditional Western metaphysicians based their metaphysical systems upon their experiences of altered states of consciousness (ASCs). It poses the question: what state of consciousness would be necessary for the metaphysician to actually experience "reality" in the way that he describes it? It specifically discusses evidence in the philosophical writings of Plato, Berkeley, Schopenhauer and Hegel which strongly suggests that they experienced various non-ordinary planes of "reality" during certain ASCs.;It is argued that Plato directly experienced the non-ordinary realm of the eternal Ideas (Level Three). Berkeley's metaphysical claims about the unreality of matter and the dependence of the entities in the everyday world (Level One) upon the mind or soul for their existence are grounded in his direct experience of the soul (Level Two) during a worldless ASC. Schopenhauer's description of the aesthetic experience of the Platonic Ideas (Level Three) is discussed as a perceptual form of concentrative meditation. Hegel's fundamental metaphysical concept of the Universal Mind of God or Absolute Spirit is rooted in his mystical experiences of Level Four. His non-Aristotelian form of logic is described as a "state-specific logic," i.e., a form of logic which is rooted in the experience of a specific ASC.;It is argued that "analytic" philosophers have misunderstood the experiential nature of traditional metaphysical language. Some of the implications of this experiential approach to philosophy are explored in terms of the notion of "state-specific metaphysical systems.";Four different metaphysical planes or levels of "reality" are presented: the everyday material world (Level One), the eternal soul (Level Two), the archetypal Platonic Ideas or essences (Level Three) and the Divine Mind of God (Level Four), which is identified with the mystical godhead.