The idea that cognitive processes can be meaningfully classified as conscious or unconscious has a long history in philosophy and psychology (see Ellenberger 1970: Erdelyi 1985; Perry and Laurence 1984, for reviews). However, even though many experimental reports during the past 100 years claim to demonstrate perception, Ieaming, or memory without conscious awareness, the distinction between conscious and unconscious ’ processes remains highly controversial. For example, the same empirical findings that Holender 1986 concludes provide little or no evidence for unconscious perception are considered by other reviewers (e.g. Dixon 1981) as conclusive and overwhelming documentation of the validity of perception without awareness. ln an attempt to explain this puzzling state of affairs, Dixon 1981 states that'. . . research on closed mindedness and related traits suggests the possibility that those people with rigid belief systems, who feel threatened by the loss of control implied by subliminal perception, might be just the sort to create a milieu in which it fails to occur' (p. 200). Dixon's critical evaluation of his theoretical rivals’ personalities instead of their arguments represents a dangerous trend because it promotes a futile debate between 'believers' :nd 'non-believers' that has very little to do with empirical evidence. We do not deny that belief systems and private epistemological and existential theories held by investigators contribute both to the controversy and to the fascination surrounding this area of research (see Crowder 1986 for candid and humorous autobiographical comments). However, while such issues may constitute an intriguing case study in the sociology...