caption known death_date death_place birth_place image_size nationality name birth_date image article_title birth_name occupation
1989 photo psychedelic therapy 31 may 1996 los angeles , california united states springfield , massachusetts united states 172px american timothy leary 22 october 1920 timothy-leary-los-angeles-1989 . jpg timothy leary
 timothy francis leary psychologist writer
timothy leary

timothy francis leary -lrb- october 22 , 1920 -- may 31 , 1996 -rrb- was an american psychologist and writer known for advocating psychedelic drugs .
leary conducted experiments under the harvard psilocybin project during american legality of lsd and psilocybin , resulting in the concord prison experiment and the marsh chapel experiment .
leary and his associate richard alpert were fired by harvard university amid controversy surrounding such drugs -lrb- although some have claimed that the experiments produced useful data -rrb- .
leary believed that lsd showed therapeutic potential for use in psychiatry .
he popularized catchphrases that promoted his philosophy , such as `` turn on , tune in , drop out '' , `` set and setting '' , and `` think for yourself and question authority '' .
he also wrote and spoke frequently about transhumanist concepts involving space migration , intelligence increase , and life extension -lrb- smi ² le -rrb- , and developed the eight-circuit model of consciousness in his book `` exo-psychology '' -lrb- 1977 -rrb- .
during the 1960s and 1970s , he was arrested often enough to see the inside of 29 different prisons worldwide .
president richard nixon once described leary as `` the most dangerous man in america '' .
