The essay “The Sorcerer and His Magic” by Claude Lévi-Strauss, specifically the part about the shaman Quesalid, is of interest to anyone who considers themselves a skeptic or a rationalist.

It has it all! Proto-scientific method and experimentation, as seen in the episode with the Koskimo shamans. Doubt and corruption… But what at first appears to be corruption may, in fact, be a more nuanced, albeit incorrect, interpretation of the world.

One is reminded of Paracelsus and his likes, who, before the invention of the modern scientific method, lived in a strange semi-magical world, yet still held ideas we cannot dismiss today, such as the discovery of zinc or the recognition of antisepsis at a time when wounds were often treated with cow dung. Or perhaps he reminds us of modern psychologists, who conduct research in a field where the ontology is not yet settled and everything seems blurry, as if immersed in an epistemic fog.

There is also going mad for epistemic reasons and dying of shame…

I am reproducing the relevant part of the essay as is:

We must consider at greater length another especially valuable document, which until now seems to have been valued solely for its linguistic interest. I refer to a fragment of the autobiography of a Kwakiutl Indian from the Vancouver region of Canada, obtained [at the turn of the century] by Franz Boas.

Quesalid (for this was the name he received when he became a sorcerer) did not believe in the power of the sorcerers — or, more accurately, shamans, since this is a better term for their specific type of activity in certain regions of the world. Driven by curiosity about their tricks and by the desire to expose them, he began to associate with the shamans until one of them offered to make him a member of their group. Quesalid did not wait to be asked twice, and his narrative recounts the details of his first lessons, a curious mixture of pantomime, prestidigitation, and empirical knowledge, including the art of simulating fainting and nervous fits, the learning of sacred songs, the technique for inducing vomiting, rather precise notions of auscultation and obstetrics, and the use of "dreamers" — that is, spies who listen to private conversations and secretly convey to the shaman bits of information concerning the origins and symptoms of the ills suffered by different people. Above all, he learned the ars magna of one of the shamanistic schools of the Northwest Coast: The shaman hides a little tuft of down in a corner of his mouth, and he throws it up, covered with blood, at the proper moment—after having bitten his tongue or made his gums bleed—and solemnly presents it to his patient and the onlookers as the pathological foreign body extracted as a result of his sucking and manipulations.

His worst suspicions confirmed, Quesalid wanted to continue his inquiry. But he was no longer free. His apprenticeship among the shamans began to be noised about, and one day he was summoned by the family of a sick person who had dreamed of Quesalid as his healer. This first treatment (for which he received no payment, any more than he did for those which followed, since he had not completed the required four years of apprenticeship) was an outstanding success. Although Quesalid came to be known from that moment on as a "great shaman," he did not lose his critical faculties. He interpreted his success in psychological terms — it was successful “because he [the sick person] believed strongly in his dream about me.” A more complex adventure made him, in his own words, "hesitant and thinking about many things." Here he encountered several varieties of a "false supernatural," and was led to conclude that some forms were less false than others — those, of course, in which he had a personal stake and whose system he was, at the same time, surreptitiously building up in his mind. A summary of the adventure follows.

While visiting the neighboring Koskimo Indians, Quesalid attends a curing ceremony of his illustrious colleagues of the other tribe. To his great astonishment he observes a difference in their technique. Instead of spitting out the illness in the form of a "bloody worm" (the concealed down), the Koskimo shamans merely spit a little saliva into their hands, and they dare to claim that this is "the sickness." What is the value of this method? What is the theory behind it? In order to find out "the strength of the shamans, whether it was real or whether they only pretended to be shamans" like his fellow tribesmen, Quesalid requests and obtains permission to try his method in an instance where the Koskimo method has failed. The sick woman then declares herself cured.

And here our hero vacillates for the first time. Though he had few illusions about his own technique, he has now found one which is more false, more mystifying, and more dishonest than his own. For he at least gives his clients something. He presents them with their sickness in a visible and tangible form, while his foreign colleagues show nothing at all and only claim to have captured the sickness. Moreover, Quesalid's method gets results, while the other is futile. Thus our hero grapples with a problem which perhaps has its parallel in the development of modern science. Two systems which we know to be inadequate present (with respect to each other) a differential validity, from both a logical and an empirical perspective. From which frame of reference shall we judge them? On the level of fact, where they merge, or on their own level, where they take on different values, both theoretically and empirically?

Meanwhile, the Koskimo shamans, "ashamed" and discredited before their tribesmen, are also plunged into doubt. Their colleague has produced, in the form of a material object, the illness which they had always considered as spiritual in nature and had thus never dreamed of rendering visible. They send Quesalid an emissary to invite him to a secret meeting in a cave. Quesalid goes and his foreign colleagues expound their system to him: "Every sickness is a man: boils and swellings, and itch and scabs, and pimples and coughs and consumption and scrofula; and also this, stricture of the bladder and stomach aches. ...As soon as we get the soul of the sickness which is a man, then dies the sickness which is a man. Its body just disappears in our insides.” If this theory is correct, what is there to show? And why, when Quesalid operates, does “the sickness stick to his hand"? But Quesalid takes refuge behind professional rules which forbid him to teach before completing four years of apprenticeship, and refuses to speak. He maintains his silence even when the Koskimo shamans send him their allegedly virgin daughters to try to seduce him and discover his secret.

Thereupon Quesalid returns to his village at Fort Rupert. He learns that the most reputed shaman of a neighboring clan, worried about Quesalid’s growing renown, has challenged all his colleagues, inviting them to compete with him in curing several patients. Quesalid comes to the contest and observes the cures of his elder. Like the Koskimo, this shaman does not show the illness. He simply incorporates an invisible object, “what he called the sickness” into his head-ring, made of bark, or into his bird-shaped ritual rattle. These objects can hang suspended in mid-air, owing to the power of the illness which “bites” the house-posts or the shaman’s hand. The usual drama unfolds. Quesalid is asked to intervene in cases judged hopeless by his predecessor, and he triumphs with his technique of the bloody worm.

Here we come to the truly pathetic part of the story. The old shaman, ashamed and despairing because of the ill-repute into which he has fallen and by the collapse of his therapeutic technique, sends his daughter to Quesalid to beg him for an interview. The latter finds his colleague sitting under a tree and the old shaman begins thus: “It won't be bad what we say to each other, friend, but only I wish you to try and save my life for me, so that I may not die of shame, for I am a plaything of our people on account of what you did last night. I pray you to have mercy and tell me what stuck on the palm of your hand last night. Was it the true sickness or was it only made up? For I beg you have mercy and tell me about the way you did it so that I can initiate you. Pity me, friend.”

Silent at first, Quesalid begins by calling for explanations about the feats of the head-ring and the rattle. His colleague shows him the nail hidden in the headring which he can press at right angles into the post, and the way in which he tucks the head of his rattle between his finger joints to make it look as if the bird were hanging by its beak from his hand. He himself probably does nothing but lie and fake, simulating shamanism for material gain, for he admits to being “covetous for the property of the sick men.” He knows that shamans cannot catch souls, “for... we all own a soul”; so he resorts to using tallow and pretends that “it is a soul... that white thing... sitting on my hand.” The daughter then adds her entreaties to those of her father: “Do have mercy that he may live.” But Quesalid remains silent. That very night, following this tragic conversation, the shaman disappears with his entire family, heartsick and fearful of the community, who think that he may be tempted to take revenge. Needless fears: He returned a year later, but both he and his daughter had gone mad. Three years later, he died.

And Quesalid, rich in secrets, pursued his career, exposing the impostors and full of contempt for the profession. “Only one shaman was seen by me, who sucked a sick man and I never found out whether he was a real shaman or only made up. Only for this reason I believe that he is a shaman; he does not allow those who are made well to pay him. I truly never once saw him laugh.” Thus his original attitude has changed considerably. The naive skepticism of the free thinker has given way to more moderate feelings. Real shamans do exist. And what about him? At the end of the narrative we cannot tell, but it is evident that he carries on his craft conscientiously, takes pride in his achievements, and warmly defends the technique of the bloody down against all rival schools. He seems to have completely lost sight of the fallaciousness of the technique which he had so disparaged at the beginning.