From the top of an Aztec pyramid, human blood ran down the steps in streams. Heads rolled, non-stop, especially around the solstice. The priests doing the work were eating psilocybin mushrooms without a break, and so were the Maya priests.
Mikhail Vishnevsky is a mycologist, a military doctor and the author of more than twenty books on fungi. He brings up the pyramids to answer a story that biologists find easy to love and hard to defend: Terence McKenna's Stoned Ape theory, in which mushrooms made early humans gentle. By that story the priests should have been the calmest people alive. Nobody on those pyramids was lowering their ego or giving up aggression.
The pyramids change what you hear the next time someone says a psychedelic makes people kinder. Vishnevsky's point is that the mushroom doesn't pick the belief. It turns up the volume on the one you bring. A modern conservative soldier who got psilocybin from a doctor would take it gladly, and he wouldn't mellow. He would walk out more sure of his reactionary views than he walked in.
McKenna's chain of reasoning, as Vishnevsky retells it, starts with a paper by the mathematician Robert Fisher. Fisher reported that psilocybin changes how certain muscles of the human eye focus. That is plain physiology: add a little psilocybin, some muscles contract. McKenna decided it meant sharper sight. Vishnevsky has little patience for that. The mushroom changes vision, he says, and the eyewitnesses lie about how, though he can well imagine what they lie about.
From there McKenna built the rest. Drought hit Africa, the herds moved on, and the early humans followed them. They ate the mushrooms that grew in the dung. Better eyes let them stand above the grass. Once they gathered, the mushrooms cut their ego and their aggression, made them chattier and more erotic, and out of that came music, poems, art and religion. Vishnevsky finds the whole thing funny, as a biologist, and says it works against biology.
The flaw is in who was eating. In the psychedelic sixties the people taking mushrooms were already inclined to harmony: anti-government, liberal about nature, hippies. The drug looked peaceful because the sample was peaceful.
Now it's clear that psilocybin has on people the effect they already have in them, and simply amplifies, smears or concentrates it.
А сейчас уже понятно, что псилоцибин оказывает такое действие на тех людей, какое у них и так уже есть, и просто его усиливает, размазывает или концентрирует.
— Mikhail Vishnevsky, Gleb Solomin Podcast, 68:13
Psychedelics, he says, are "resonators". Whatever faint or buried thought is already in your head gets strengthened, and so does the sense of belonging to a group that thinks the same way. A study by Otto Simonsson in the Journal of Psychopharmacology in May 2026 looked at three sets of data and found no significant change in authoritarian attitudes after psychedelic use.
And yet Vishnevsky's verdict on McKenna is that he guessed right, for a different reason. Humans are 84 times more sensitive to psilocybin than the other primates. Evolution is stingy, he says, and rebuilding a species is like rebuilding an airplane in flight. To change the wings you tear off a piece of the skin or rip out a seat, and if the change is wrong, the plane falls. A sensitivity 84 times higher was paid for, so it was needed for something.
Vishnevsky's bet is that the something was belief. A person who eats the mushroom sees sound and hears colour. Nothing about it feels induced. It feels like the way things are. Scientists now have a name for this, "biologically induced truth", and it came to a mind that was barely starting to think. In a band, the one who ate stands above the ones who didn't, a future priest, a person who has understood something. The effect could not have been overestimated.
It also takes away the fear of death, a part of almost any religion: you dissolve into everything, and there is no end because there was no beginning. The molecule has no preference about which truth it delivers.
How it works in the brain, nobody can say yet. Vishnevsky expects the biochemistry to be laid out within about ten years, though he calls that a gut feeling.
