In the late 1950s, psychologist Milton Rokeach was gripped by an eccentric plan. He gathered three psychiatric patients, each with the delusion that they were Jesus Christ, to live together for two years in Ypsilanti State Hospital to see if their beliefs would change. The early meetings were stormy. “You oughta worship me, I’ll tell you that!” one of the Christs yelled. “I will not worship you! You’re a creature! You better live your own life and wake up to the facts!” another snapped back. “No two men are Jesus Christs. … I am the Good Lord!” the third interjected, barely concealing his anger.

Frustrated by psychology’s focus on what he considered to be peripheral beliefs, like political opinions and social attitudes, Rokeach wanted to probe the limits of identity. He had been intrigued by stories of Secret Service agents who felt they had lost contact with their original identities, and wondered if a man’s sense of self might be challenged in a controlled setting. Unusually for a psychologist, he found his answer in the Bible. There is only one Son of God, says the good book, so anyone who believed himself to be Jesus would suffer a psychological affront by the very existence of another like him. This was the revelation that led Rokeach to orchestrate his meeting of the Messiahs and document their encounter in the extraordinary (and out-of-print) book from 1964, The Three Christs of Ypsilanti.

Although by no means common, Christ conventions have an unexpectedly long history. In his commentary to Cesare Beccaria’s essay “Crimes and Punishments,” Voltaire recounted the tale of the “unfortunate madman” Simon Morin who was burnt at the stake in 1663 for claiming to be Jesus. Unfortunate it seems, because Morin was originally committed to a madhouse where he met another who claimed to be God the Father, and “was so struck with the folly of his companion that he acknowledged his own, and appeared, for a time, to have recovered his senses.” The lucid period did not last, however, and it seems the authorities lost patience with his blasphemy. Another account of a meeting of the Messiahs comes from Sidney Rosen’s book My Voice Will Go With You: The Teaching Tales of Milton H. Erickson. The renowned psychiatrist apparently set two delusional Christs in his ward arguing only for one to gain insight into his madness, miraculously, after seeing something of himself in his companion. (“I’m saying the same things as that crazy fool is saying,” said one of the patients. “That must mean I’m crazy too.”)

These tales are surprising because delusions, in the medical sense, are not simply a case of being mistaken. They are considered to be pathological beliefs, reflecting a warped or broken understanding that is not, by definition, amenable to being reshaped by reality. One of most striking examples is the Cotard delusion, under which a patient believes she is dead; surely there can be no clearer demonstration that simple and constant contradiction offers no lasting remedy. Rokeach, aware of this, did not expect a miraculous cure. Instead, he was drawing a parallel between the baseless nature of delusion and the flimsy foundations we use to construct our own identities. If tomorrow everyone treats me as if I have an electronic device in my head, there are ways and means I could use to demonstrate they are wrong and establish the facts of the matter—a visit to the hospital perhaps. But what if everyone treats me as if my core self were fundamentally different than I believed it to be? Let’s say they thought I was an undercover agent—what could I show them to prove otherwise? From my perspective, the best evidence is the strength of my conviction. My belief is my identity.

In one sense, Rokeach’s book reflects a remarkably humane approach for its era. We are asked to see ourselves in the psychiatric patients, at a time when such people were regularly locked away and treated as incomprehensible objects of pity rather than individuals worthy of empathy. Rokeach’s constant attempts to explain the delusions as understandable reactions to life events require us to accept that the Christs have not “lost contact” with reality, even if their interpretations are more than a little uncommon.

But the book makes for starkly uncomfortable reading as it recounts how the researchers blithely and unethically manipulated the lives of Leon, Joseph, and Clyde in the service of academic curiosity. In one of the most bizarre sections, the researchers begin colluding with the men’s delusions in a deceptive attempt to change their beliefs from within their own frame of reference. The youngest patient, Leon, starts receiving letters from the character he believes to be his wife, “Madame Yeti Woman,” in which she professes her love and suggests minor changes to his routine. Then Joseph, a French Canadian native, starts receiving faked letters from the hospital boss advising certain changes in routine that might benefit his recovery. Despite an initially engaging correspondence, both the delusional spouse and the illusory boss begin to challenge the Christs’ beliefs more than is comfortable, and contact is quickly broken off.

In fact, very little seems to shift the identities of the self-appointed Messiahs. They debate, argue, at one point come to blows, but show few signs that their beliefs have become any less intense. Only Leon seems to waver, eventually asking to be addressed as “Dr Righteous Idealed Dung” instead of his previous moniker of “Dr Domino dominorum et Rex rexarum, Simplis Christianus Puer Mentalis Doctor, reincarnation of Jesus Christ of Nazareth.” Rokeach interprets this more as an attempt to avoid conflict than a reflection of any genuine identity change. The Christs explain one another’s claims to divinity in predictably idiosyncratic ways: Clyde, an elderly gentleman, declares that his companions are, in fact, dead, and that it is the “machines” inside them that produce their false claims, while the other two explain the contradiction by noting that their companions are “crazy” or “duped” or that they don’t really mean what they say.

In hindsight, the Three Christs study looks less like a promising experiment than the absurd plan of a psychologist who suffered the triumph of passion over good sense. The men’s delusions barely shifted over the two years, and from an academic perspective, Rokeach did not make any grand discoveries concerning the psychology of identity and belief. Instead, his conclusions revolve around the personal lives of three particular (and particularly unfortunate) men. He falls back—rather meekly, perhaps—on the Freudian suggestion that their delusions were sparked by confusion over sexual identity, and attempts to end on a flourish by noting that we all “seek ways to live with one another in peace,” even in the face of the most fundamental disagreements. As for the ethics of the study, Rokeach eventually realized its manipulative nature and apologized in an afterword to the 1984 edition: “I really had no right, even in the name of science, to play God and interfere round the clock with their daily lives.”

Although we take little from it scientifically, the book remains a rare and eccentric journey into the madness of not three, but four men in an asylum. It is, in that sense, an unexpected tribute to human folly, and one that works best as a meditation on our own misplaced self-confidence. Whether scientist or psychiatric patient, we assume others are more likely to be biased or misled than we are, and we take for granted that our own beliefs are based on sound reasoning and observation. This may be the nearest we can get to revelation—the understanding that our most cherished beliefs could be wrong.

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