In 1799, the London Medical and Physical Journal published a landmark case study. Its author, Dr. Everard Brande, related the story of a family bizarrely and simultaneously afflicted with everything from “flight vertigo” to “fits of immoderate laughter.” The laughing patient was Edward, an eight-year-old boy, who couldn’t stop finding the situation so funny, “nor could the threats of his father or mother refrain him.”

Given the disciplinary attitudes of that era, these were no idle threats. What made Edward laugh despite his better judgment? Early that October morning, his father had gone foraging for breakfast, as he often did, at Green Park, in central London. Returning from this former leper burial ground with no more than “a tea saucerful” of what “he supposed to be small mushrooms,” he made a stew. Edward, the youngest child, consumed more than his share. Soon he began to hallucinate. His sisters and parents followed suit.

Dr. Brande’s article, “On A Poisonous Species of Agaric,” correctly identified the catalyst for the family’s eclectic symptoms (dilated pupils, detachment from reality, delirium) as an unusual if common-looking fungus, Psilocybe semilanceata. Today, psychonauts the world over seek it out for a good time. Long before the turn of the nineteenth century, the Aztec knew and prized the effects of teonanácatl, their “godly mushroom,” but until quite recently, Europeans only ever ate it by accident.

How do we experience intoxication without intent? The mind requires a framing device to judge a bout of altered consciousness for what it really is. Otherwise, as in the archetypal “bad trip” associated with potent psychoactive compounds, we may come to believe ourselves forever altered, stuck in some alien state, never to touch solid ground again. Edward’s father, for example, “complained that everything appeared black, then wholly disappeared,” and of “universal numbness and coldness, with great dejection, and a firm persuasion that he was dying.”

Any number of drugs can flood our consciousness with faulty perceptions. And if the sensory apparatus isn’t filtering properly, you receive an excess of environmental information when you’re least equipped to handle it. This helps explain why the same drug can generate wildly different results—a CIA field agent whose coffee is secretly spiked with LSD might run screaming into the street, while college buddies can drop a tab and spend all day giggling in a grassy field. The recreational drug user in theory understands that she is messing with her own head. The man who doesn’t know he’s been dosed may conclude that existence has been usurped by mere chaos.

Aldous Huxley in 1954 wrote as eloquently as one can about taking mescaline, which accomplishes more or less what Psilocybe semilanceata does. He had a more pleasant day than young Edward’s family, however, and in The Doors of Perception quoted Cambridge philosopher Dr. C. D. Broad in describing the mental processes modified:

Each person is at each moment capable of remembering all that has ever happened to him and of perceiving everything that is happening everywhere in the universe. The function of the brain and nervous system is to protect us from being overwhelmed and confused by this mass of largely useless and irrelevant knowledge, by shutting out most of what we should otherwise perceive or remember at any moment, and leaving only that very small and special selection which is likely to be practically useful.

“According to such a theory,” Huxley continues, “each one of us is potentially a Mind at Large. But in so far as we are animals, our business is at all costs to survive. To make biological survival possible, Mind at Large has to be funneled through the reducing valve of the brain and nervous system.” Huxley notes this precarious balance:

The schizophrenic is like a man permanently under the influence of mescalin, and therefore unable to shut off the experience of a reality which is he is not holy enough to live with, which he cannot explain away because it is the most stubborn of primary facts, and which, because it never permits him to look at the world with merely human eyes, scares him into interpreting its unremitting strangeness, its burning intensity of significance, as the manifestations of a human or even cosmic malevolence …

Dr. Gerald D’Arcy Klee, my grandfather, has glimpsed that malevolence. When I last visited, he was digging up mementos of his public health and psychiatric work in the postwar years for institutions like the U.S. Medical Center for Federal Prisoners and Johns Hopkins University. He showed me a copy of a letter written to President Nixon in his first term, urging him to condemn the potential weaponization of LSD (a cousin to Psilocybe semilanceata). A decade before, he’d tested the ergot derivative on soldiers, writing clear-eyed reports such as “Influence of lysergic acid diethylamide (LSD-25) on subjective time” and “Lysergic acid diethylamide (LSD-25) and ego functions.” Out of ethical concerns, he was obligated to sample the stuff for himself.

“Did he ever say how it was?” I once asked my dad.

“Scary,” he replied.

Fair enough: a military lab is no one’s idea of a fun place to get high. But it was not immediately obvious that LSD’s effects were so wide-ranging and individuated, easily reshuffled by mood and circumstance. What Dr. Klee explored were the particular responses of certain LSD-dosed soldiers to their subservient position in a scientific inquiry, Trapped like a mouse in a Skinner box, each had his cognitive architecture manipulated and tested accorded to a strict protocol. You can see how it might be tricky to extrapolate your findings from there to Woodstock.

Which may be why, ultimately, Nixon never had to address the question of weaponized LSD. A few investigative journalists have offered possible evidence of drug-based mind-control research—the mysterious 1953 death of Dr. Frank Olson, a government biochemist; the mass hysteria in 1951 of the French village Point-Saint-Esprit, which may also have been the result of ergot poisoning from the local baker’s bread. If anything, though, these events demonstrated that you couldn’t hope to anticipate your enemy’s response to forced or unfamiliar inebriation. LSD’s disorienting influence doesn’t seem reducible to total bliss or a total freak-out—it’s a coin with those two sides, and everyone tends to get stuck on one of them, as evidenced by a long mid-century debate between my grandfather and Timothy Leary. From a Playboy interview in 1966:

PLAYBOY: Dr. Gerald Klee of the National Institute of Mental Health has written: “Those who say LSD expands consciousness would have the task of defining the terms. By any conventional definition, I don’t think it does expand the consciousness.” What do you think?

LEARY: Well, he’s using the narrow, conventional definition of consciousness that psychiatrists have been taught: that there are two levels of consciousness—sleep and symbolic normal awareness. Anything else is insanity. So by conventional definition, LSD does not expand symbolic consciousness; thus, it creates psychosis. In terms of his conventional symbol game, Dr. Klee is right. My contention is that his definition is too narrow, that it comes from a deplorable, primitive and superstitious system of consciousness. My system of consciousness attested to by the experience of hundreds of thousands of trained voyagers who’ve taken LSD defines many different levels of awareness.

That “awareness” is telling. An awareness of the action, the risks and the potential benefits. Or, as Leary points out, an awareness of what we are willing to believe. Beyond that, an awareness of one’s purest self.

For all the energy Dr. Klee invested in the LSD conundrum, his most frightening paper was about plain old Mary Jane. “Marihuana psychosis,” from a 1969 issue of The Psychiatric Quarterly, concerns a twenty-six-year-old man who smokes “less than two marihuana cigarettes” and suffers a psychotic break. In his own words, the patient recounts Dantean visions of hell and purgatory, spontaneous threats of violence against his girlfriend and a sense of impending annihilation. Background on the subject, however, reveals previous emotional trauma, and a recent analysis titled “Comorbidity between cannabis use and psychosis” concluded that a predisposition to mental illness underlies these disturbing episodes. While hallucinogens can’t be said to bestow madness, they may certainly wake the dormant kind. 

Still, the marijuana smoker came back from everlasting torture and pain; my grandfather came back from his descent into irrational, bottomless fear; Edward and his family came back from that curious, unlikely trip. Dr. Brande credited his prescription, an “emetric solution to excite vomiting,” with their recovery. Water and a few hours’ quiet coddling might have done the trick just as well. The idea of temporary suffering, sadly, holds little comfort for those drowning in the infinite.