Correlation is not Causation. But it's also not not Causation. How today's Dope Apologists are just like Big Tobacco apologists 60 years ago.

You can't blame the Cannabis Comment Warriors for ceaselessly pointing out that 'correlation isn't causation' . They are desperate.  

 

For they are in much the same position that Big Tobacco was in when it first became clear that cigarette smokers were becoming ill in large numbers. The correlation was there. The cause couldn't be proved. So, rather than admitting the risk, they reached for the most complacent possible answer, so delaying the general recognition of the truth for many years.

 

The modern campaigners for Big Dope - tantalisingly close as they are to legalization - fear this topic greatly. They know very well a) that many marijuana users become mentally ill , b) that mental illness itself is extremely hard to categorize objectively and c) that the mechanism by which they become ill is currently impossible to discover, and may remain so for many years. The same was true, for a long time, of the undoubted correlation between cigarette smoking and lung cancer, and the same claim was emplyed by Big Tobacco as is now being used by the people who hope to be Big Dope.

 

They are quite right to say that correlation is not necessarily evidence of causation. But they are less keen to admit the corollary.

 

Correlation is not necessarily *not* evidence of causation, and in fact is one of the foundatons of epidemiology.

 

The great Victorian physician, John Snow, traced an outbreak of Cholera in London, in 1854, to a particular water pump,  though correlation. Medical fashion believed that Cholera was passed on through 'bad air' (interestingly, Big Tobacco for many years tried to claim - yes, they really did - that lung cancer was caused by general air pollution).  So they derided his theory.

 

Dr Snow's water sample from the affected pump didn't conclusively prove that it was the source. But when the authorities took the handle off the pump, the epidemic ended.  Now, of course, everyone knows that Snow was right. 

 

But if he had been beaten off by the 'correlation is not causation' merchants, how many more people would have had to die of cholera before he could prove it?

 

And how many more young people and their families will have their lives ruined by irreversible mental illness, while the Cananbis Lobby continues to behave in this unscrupulous and selfish fashion?