“…Very early academic research on classical hallucinogens was designed without considering the powerful influences of set (psychological state) and setting (environment) (e.g., Malitz et al, 1960; Rinkel et al, 1960; Hollister, 1961; Rümmele and Gnirss, 1961; Leuner, 1962). Subsequent research, which included more preparation and interpersonal support during the period of drug action, found fewer adverse psychological reactions, such as panic reactions and paranoid episodes, and increased reports of positively-valued experiences (Chwelos et al, 1959; Leary, 1964; Leary et al, 1963, 1964; Metzner et al 1965; Pahnke, 1969). …”