Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Irrelevant mumbo-jumbo

I was sorely disappointed by this tome. It consists of a very padded series of annecdotal trip reports, followed by some nebulous and unsubstantiated speculation on the role of DMT in the brain as a facilitator of birth and death. As a doctor, he appears to pay scant regard for the physical and mental health of his subjects. Ethical and regulatory approval for in-vivo research with psychedelic compounds is hard enough to get without crap like this. Stick to science, not this New-Age waffle. Waste of money. Do not buy it.