New Worlds: The Art and Science of Diagnosis

(This month’s medical essays will largely be focused on matters of anatomy or surgery, but this first one is going to talk more broadly about diagnosis of both injuries and illness. If you’re feeling too stressed out by covid, don’t feel guilty about giving this one a pass.)

Before you can treat a patient, you have to know what’s wrong with them.

In broad terms, there are two components to making this work: observation and analysis. The former involves gathering information through a variety of methods; the latter involves comparing that information to what the physician knows in order to find a match. That latter part gets very technical, very fast, and I’m not remotely qualified to discuss it, so our focus here will mostly be on the “observation” part of the equation — because how that gets done is highly variable and culturally shaped.

Let’s use modern Western medicine as our starting point, since that’s what the bulk of my readers are likely to be familiar with. A physician in this system will gather multiple kinds of information by multiple means. They often collect some vital stats, like body weight, blood pressure, and temperature, then ask the patient to self-report on symptoms. Following that, they’ll often conduct simple tests, such as various kinds of movements if the problem is related to muscles or joints, palpation if it’s an internal organ, or using tools to examine eyes, ears, or the throat. In many cases they already have a generalized medical history, but they may ask more targeted questions, both on the individual level (when did the symptoms begin,; did the patient do X, Y, or Z in the recent past) and the familial (have any close relatives been diagnosed with a particular ailment). If the circumstances seem to warrant it, they’ll order more specialized tests: scans like x-rays or MRIs, lab work like blood tests and throat cultures, and so forth. At any step along the way, the physician may arrive at a diagnosis, but in complicated situations that may take a long time to arrive — or it may never.

Fast-forward to the science fictional future! Writers of this type of fiction often assume that the collection of data will be vastly more streamlined, as epitomized by the Star Trek “tricorder.” Wave a device over the patient or have them lie down on some kind of scanning bed, and receive all the information you might need in mere seconds! I think this approach is heavily shaped by episodic TV, where a character’s illness often forms the plot of that episode, and thus needs to be recognized, diagnosed, and treated before the credits roll. Even if it’s a more ongoing plot, there isn’t a lot of interest value in saying the characters have to wait three days to get the lab results back. (See also police procedurals, where crime labs deliver their reports nigh instantaneously. Would that were true in reality!) But this approach robs medical plots of much of their complexity, too: the mystery usually lies only in figuring out how to treat the problem, not what the problem might be in the first place.

Rewind the clock to the historical past, and the world of diagnosis gets a lot weirder. Credit where it is due: the learned doctors of yore were extremely good at observation. They didn’t have access to our high-tech diagnostic tests, or even to simple tools like the stethoscope (invented in 1816 by a French physician who was too embarrassed to put his ear against a female patient’s chest), but they absolutely knew how to pay attention to symptoms. They observed eyes, tongues, skin, feces, and urine — even going so far as to taste the latter, which may sound disgusting, but it’s a perfectly valid method of detecting things like the excessive sweetness that characterizes diabetes. Changes in sleep, appetite, sex drive, balance, and other behavioral signals were also fodder for their analysis.

Of course, that analysis and even the method by which observation was performed would be shaped by their understanding of medicine. And as we discussed in Year Three, the models for that were broken clocks that managed to be right just often enough for people to go on consulting them. Dreams, for example, might be seen as a vital tool in diagnosis; one of the major functions of a temple to the Greek medical god Asclepius was “incubation,” sleeping on the premises to receive dreams that would point to a cure. So too with omens like the flight of birds. But it wasn’t all what a modern doctor would consider superstitious nonsense; there was a great deal of practical data involved, to the point where we can often make reasonable guesses at the causes for individual deaths or community epidemics, based on the information gleaned from historical records.

So what does this mean for our fiction? Obviously what I’ve been describing here is the ideal, whether it be modern, futuristic, or historical: a skilled physician with the best tools available, who knows what to pay attention to and what information might be relevant. But the world (be it modern, futuristic, or historical) is also filled with incompetents and quacks who might be more interested in moving on to the next patient or squeezing as much money as possible from this one. There’s plenty of narrative mileage to be had from bad medicine — sometimes more than the good kind.

Even on the good side of the equation, though, you can still have story. It just requires that you pay attention to the various components that go into a medical plot, and don’t skip over the early stages in favor of getting to the part where the ailment is being treated. Even if we can build machines that not only collect vital stats but also perform x-rays, MRIs, EEGs, EKGs, blood tests, and more, all in less than a minute . . . that’s a huge pile of information to sort through. Which parts of it are relevant? You can get around that question by saying there’s an equally advanced computer doing the analysis — but is a computer really going to be free of the biases and blind spots a human might have? We’ve either programmed the thing, or it’s intelligent enough to learn (and make mistakes) on its own. Just because you can say that yes, it does everything perfectly, doesn’t mean that’s the most interesting narrative possibility.

And I think this side of things is sadly neglected in fantasy. I learned about the tasting of urine from Guy Gavriel Kay’s The Lions of Al-Rassan, based on Moorish Spain; in Chinese historical and fantastical dramas, pulse-taking is a ubiquitous diagnostic tool. But where are the fictional analogues, leveraging the magic system of the story for these purposes? I don’t mean the supernatural equivalent of a tricorder, but smaller applications for specific purposes. Mary Robinette Kowal’s Glamourist Histories contain one of the few exceptions I can think of; she has a character dealing with a medical emergency figure out that he can use a form of “distance vision” magic to see where his patient is bleeding out internally. Not all systems are amenable to being used for medical observation, but some of them are, especially if you start thinking creatively.

But then, relatively few fantasy authors are also doctors. So we’re not particularly inclined by our own background and experience to think about such things, which is the necessary prerequisite to inventing them. That doesn’t mean we can’t try, though!



About Marie Brennan

Marie Brennan is a former anthropologist and folklorist who shamelessly pillages her academic fields for inspiration. She recently misapplied her professors' hard work to the short novel Driftwood and Turning Darkness Into Light, a sequel to the Hugo Award-nominated Victorian adventure series The Memoirs of Lady Trent. She is the author of several other series, over sixty short stories, and the New Worlds series of worldbuilding guides; as half of M.A. Carrick, she has written The Mask of Mirrors, first in the Rook and Rose trilogy. For more information, visit, Twitter @swan_tower, or her Patreon.


New Worlds: The Art and Science of Diagnosis — 3 Comments

  1. Pingback: New Worlds: The Art and Science of Diagnosis - Swan Tower

  2. When I was researching the history of medicine for Sold for Endless Rue, which takes place at in part at the first European medical School in Salerno, Italy, I read a lot about diagnosis, which was truly the most sophisticated aspect of medicine at the time. Somewhere in my research files I have a long list of what a physician in the Scuola Medicina expected to be able to determine from urine, by the color, the taste, the texture (oily, sandy, thin), and smell, and by modern standards it was largely correct. The explanations for why someone might have an elevated pulse rate or jaundice might seem laughable to us now, and frequently hampered the ability to do any real good.

  3. The plagues of Galen and Cyprian were named after the men who gave us a detailed description of the disease symptoms.

    Yet, we still have arguments about which was the first outbreak of measles and which of smallpox, or even whether they were the first outbreaks of measles and smallpox.