 Major criticisms came from Steven T. Katz in his influential series of publications on mysticism and philosophy, and from Wayne Proudfoot in his "Religious experience" (1985).Masson and Masson criticised Stace for using a "buried premise," namely that mysticism can provide valid knowledge of the world, equal to science and logic.A similar criticism has been voiced by Jacob van Belzen toward Hood, noting that Hood validated the existence of a common core in mystical experiences, but based on a test which presupposes the existence of such a common core, noting that "the instrument used to verify Stace's conceptualization of Stace is not independent of Stace, but based on him."