This seems like just another example of an academic ranting about a subject in which he is unqualified, until we get to the money quote:
"As far Moses on Mount Sinai is concerned, it was either a supernatural cosmic event, which I don't believe, or a legend, which I don't believe either, or finally, and this is very probable, an event that joined Moses and the people of Israel under the effect of narcotics," [Benny] Shanon told Israeli public radio on Tuesday.
It's a perfect example of the scientific pitfall of naturalism. One of the bedrock tenets of modern science is that science deals with the natural, not the supernatural. Thus, when performing scientific analysis, a researcher usually assumes that there is no supernatural cause for observed events. That's all well and good, and the assumption is usually understood and factored (explicitly or implicitly) into the conclusions of the research.
The pitfall comes when the researcher takes this assumption for the purpose of research, and applies it to their perspective on reality. This rapidly leads to a logical fallacy called begging the question or assuming the consequent: a researcher assumes something, makes observations based on that assumption, and then uses the observations to prove the assumption. That's exactly what Benny Shanon is doing. The logical progression is basically:
- Assume that Moses had an experience on Mount Sinai.
- For the purpose of scientific analysis, assume that Moses's experience was not supernatural.
- If Moses's experience was purely natural, the most likely explanation is a religious service incorporating hallucinogens.
- Therefore, Moses was probably high on Mount Sinai.
- Therefore, Moses's experience was probably not supernatural.
See how the assumption kinda gets lost around step four, and then is magically proven at the end? Either Shanon's a bad enough scientist that he's begging the question himself, or (more likely) he's making the argument in bad faith in order to gain a little notoriety. Instead, he should be claiming, "Assuming Moses didn't meet God on Mount Sinai, he was probably on drugs" -- a statement which is not at all controversial and merits only the response, "Well, duh!"