By Professor Guy Claxton (Emeritus Professor of the Learning Sciences)
By Jacob Empson
By William Dement
By Sigmund Freud, Joyce Crick, Ritchie Robertson (Reader in German and Fellow, Reader in German and Fellow, St John's College, Oxford)
By Vera Peiffer
By Jeremy Narby
By Shine, Betty
By C. G. Jung, C. Kerenyi
By Jung, C.G.
By William S. Burroughs
By Ralph Metzner, Richard Alpert, TIMOTHY LEARY, Daniel Pinchbeck
By Michael Pollan
By Antonio Damasio
By Susan Blackmore
By Geoffrey Arthur Dudley
By J. Allan Hobson
By Claxton, Guy
By Professor Anil Seth
By Steve Biddulph
By Dabney Ewin
By Ian Oswald
By Jung, C. G.
By Robert Dilts
By Aldous Huxley
By Michael Newton, Ph.D.
By Freud, Sigmund