August 23

…the Guardian wishes the believers to disregard such subjects as psychic practices and phenomena, for these besides not being authenticated by the Writings of the Founders of the Faith, pertain mostly to the domain of conjectures. 
- Shoghi Effendi  (From a letter dated 30 March, 1938, written on behalf of Shoghi Effendi to an individual believer; ‘Letters from the Guardian to Australia and New Zealand’)