“Attempts to prove that marijuana will make you crazy have a long and undignified history in the debate over legalization and cannabis use. You seem crazy when you smoke marijuana, anti-potters decided, so it must make you crazy in a clinical way, such as (most notably and scariest) schizophrenia…
The latest study to poke holes in the blown-up fear of marijuana causing psychosis comes from the Institute of Psychiatry at King’s College London.
The study shows that a gene related to schizophrenia may lead people to want to smoke marijuana. Note that this is exactly the kind of flip of a “common understanding” that comes out of correlation studies…
“We know that cannabis increases the risk of schizophrenia. Our study certainly does not rule this out, but it suggests that there is likely to be an association in the other direction as well – that a pre-disposition to schizophrenia also increases your likelihood of cannabis use,” Robert Power, who led the study, told Reuters.”