Anyone who studies philosophy has run into the assumption that psychoactive drugs and philosophy go hand-in-hand. Really, after analytic and continental, and whatever other traditions people come up with, there could be another sect, that of “stoner philosophy,” which is something like Mister Rogers, Alan Watts and Bob Ross thrown into a peaceful blender. This is when you’re sitting around getting high, wondering if aliens exist, instead of sitting in a classroom, wondering if other people’s minds exist.
A historical study of this connection, from East to West, would probably scandalize a lot of “serious” philosophers, and show some regular inebriation, but in general, I think the two are opposed (tragically or not). Particularly, the institutionalization of philosophy, when “natural philosophy” and “moral philosophy” etc all became separated some time after Hobbes, is opposed to what it sees as a lay way of thinking about the world. As my philosophy of science professor told me – you become a philosopher when you have your doctorate.
Professional philosophers and “psychonauts” are in opposition to each other. The analytics and continentals have spent centuries building elaborate systems – developing monstrous levels of specificity, so as to make their work completely incomprehensible to the rest of the world – and earning credentials to close the gates of access. Meanwhile, the casual or professional tripper is able to buy a tab for less than $10 and experience, or imagine they experience, market-price existentialism without reading a page of Camus.
The professional philosopher sneers in bad faith at psychedelic profundity because it makes them seem irrelevant.
On the other hand, the inarticulate tripper is not in such a great place. The psychonaut rests on intuition, and is probably not equipt with the critical thinking and logical itinerary to make sense of the journey on the comedown. A trip promises insight but also promises that neither your epistemic priors nor a rational reconstruction will be enough to establish its validity – by its very nature. (Psychedelic knowledge is “revealed,” not “discovered,” right?) You might get an insight that looks good, but is bad, without you knowing it. (I wrote about this in college. Holy shit my writing was bad.)
What happens when you irrationally, psychonautically attach to an idea that’s immune to logical tinkering? If you believe something for irrational reasons you’ll hang on to it for even longer than something that you believed for rational reasons, because new rational reasons can talk you out of a logogenetic idea, but not an irrationally-formed one. Depending on the centrality of the belief, of course.
The psychonaut claims easy knowledge, but could have trouble organizing it in the other, orderly web of belief of his coldly-discovered priors. However, this kind of knowledge has taken a high prestige today, with help from accredited social figures like Steve Jobs dosing LSD. In a way, the win of casual inebriated profundity is a “people’s victory” over the esoteric, pretentious toils of the professional philosophers. If you can figure out Truth by serotonin-fucking yourself on any day of the week then there’s no need to study Heidegger… and there’s even less reason to get a PhD in phenomenology, making institutional philosophy obsolete.
So, philosophers will be opposed to the psychonauts because it trivializes their hard-earned degrees (bad faith), and trivializes all their carefully crafted logic (slightly less bad faith). Psychonauts will be opposed to the philosophers for their specialized field which must explicitly reject such spontaneous routes to knowledge. The people taking psychedelics find themselves fighting some sort of anti-scientific elitism war, doing Feyerabend’s work. The tension is worse with the professional, modern philosophical class, but still exists in general.
A survey of history would show a lot of intertwining, but ultimately, I think the newer age of philosophy has a lot more overlap with other drugs than psychedelics (specifically Epicurean as opposed to elucidatory drugs, e.g. Adderall, analgesics, cocaine) — which is its own interesting question.