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Thanks David,

I agree. As a medical doctor and research scientist with 40 years experience, I am sure that Frank is strickly correct. The case is not proven by any reasonable scientific measure. It is premature to make hard claims.However I know of many examples where "early hints" turned out to be true in the long term.

In medicine, as I'm sure in many other areas, we often use the principle of "precautionary prinicple". 

Obvious  current examples would be global warming, not proven, but sounds sensible to act anyway. Wait till it is proven beyond scientific doubt may be too late.

In my field, BSE and prions, low dose aspirin for heart attack prevention, many early results with cancer therapies, all these were proposed by zealots often decades before the science caught up with robust evidence. How many patients died or suffered because we waited for final proof before acting?

So yes, let us get robust scientific evidence before making a final judgment, but also let us look at history and see how these themes develope over decades.

Brain neuroscience is particularly difficult. I've done work with drug effects shown up on PET scans that look amazing. However, beware that what you see is what you want to see!

Keep the faith all. Science will win out eventually, with the help of a bit of human art and intuition! (but it does tend to plod on rather slowly!)

Francis