Disease and Belief
Are there any diseases of the belief system? Apparently there are: they have names like schizophrenia and bipolar disorder. These diseases (OED: “a disorder of structure or function in a human, animal, or plant”) cause the sufferer to form false and irrational beliefs, sometimes whole belief systems we label “delusional” or “crazy”. These defective beliefs can cause harm to the believer and to others (think of paranoia). But are there any contagious diseases of the belief system? We can certainly imagine such a disease: there could be a species that contracts defective beliefs by transmission from one believer to another. Giving voice to certain beliefs could cause them to be formed in another mind by a kind of automatic transmission, no convincing justification necessary. It would be possible for belief “viruses” to be concocted in a laboratory and then intentionally sent out to infect the local population. So long as the population was receptive to invasion by these agents of belief formation we can imagine them spreading according to the standard epidemiological model. The beliefs spread meme-like across the population. We could think of the contagious belief as a “mind virus” (cf. computer virus). It might be that the beliefs involve wacky ideas about the origins of the universe or other people’s motivations or the secret life of cats. We can imagine these false beliefs doing a good deal of harm (there is a movement to put down all cats). Preventative measures would be possible: don’t listen to or read any material with potentially dangerous content, keep away from others already suffering from the disease, and stay at home. Maybe a “vaccine” can be produced that immunizes people from infection: scientists inject a mild form of the disease into people so that their critical faculties become sensitized to this sort of invasion, thus reducing the chance of catching the disease in its most florid form. The principle is that once you’ve been in a cult you are not likely to join another one: you recognize the dangers and smartly walk away. Or some talk therapy might be indicated: simply tell people not to take those weird rumors seriously—point out how harmful they can be (some horrifying videos might be effective). For this species of believers, susceptible as they are, the infectious disease model would be entirely appropriate: they are prone to a disease that spreads in the usual way, and which can be managed by the standard procedures. The disease might even have a name: “beliefitis” or “assentosis” or “Wilkinson’s syndrome” (named after its discoverer). Doctors would be used to treating it, applying properly tested protocols, holding scientific conferences on the subject. For them it is a recognized branch of medicine.
I set up this imaginary case in order (of course!) to throw light on the actual human situation. For it is evident that a situation very like this obtains in the human population: people are extraordinarily susceptible to disorders of the belief system. We need to form beliefs by transmission from others (“testimony”), this being an essential part of learning, but our defenses against bad beliefs are far from stellar. If we think of ourselves as possessing a cognitive immune system, then it is a notably porous one: all sorts of cognitive pathogens get through our defenses. Rationality (logic) acts as our immunological filter, but it is routinely bypassed and outmaneuvered. Those wily belief memes slip through its defenses with alarming ease. Some people have very weak cognitive immunity, lending their assent to almost anything they hear–the crazier the better, as far as they are concerned. Just consider all those ridiculous conspiracy theories that thrive on the Internet: they have no trouble infecting the brains of people with deficient cognitive immunity. Preventative measures are in principle possible—cover your eyes in the presence of such material, wear earplugs when necessary, don’t go near other people already infected—but it is virtually impossible to get people to follow these guidelines, no matter the prestige of the prescribing authority. Conspiracy theories about the motivations of the relevant experts can easily subvert their recommendations; and a national mandate is deemed politically unacceptable. So the belief virus keeps propagating, infecting, and transmitting. If the beliefs in question concern another disease, a purely physical one, then we have a pair of diseases running in parallel: a disease of the body and a disease of the mind. Both may be lethal if the penalty for erroneous belief is death. As the physical pathogen spreads and multiplies, so too does the mental pathogen: a psychological disease accompanies the physical disease (at least for people susceptible to the belief virus). In any case, these disorders of the belief system deserve to be thought of a disease-like, as much as physical disorders are. The offending beliefs are really a type of germ (from the Latin for “seed, sprout”): that is, they act as replicative agents of disorder—mental disorder in this case. They operate just like regular harmful germs from an epidemiological perspective. Not all beliefs are disease vectors, of course, just as not all germs are (some are perfectly harmless), but some are, well, virulent. And just as a schizophrenic strikes one as cognitively disordered, so someone in the grip of wacky conspiracy theories strikes one as mentally diseased (infected, invaded). It comes in degrees, but in extreme cases the beliefs achieve delusional stature: the sufferer is living in his own crazed world, cut of from reality. This is not at all uncommon—like the common cold. In fact, it is quite difficult to avoid getting infected—one’s defenses may not be able to ward off a concerted attack. Too much time spent with the wrong people can lead almost anyone to succumb to the disease. And there is no known vaccine with anything like the necessary efficacy (a logic course can only chip away at the problem). Once the virus has flooded the memo-sphere it can create havoc (the Internet is its prime vector). Hotspots will flare up, quarantining has little impact, and the disease rages on. People’s brains become breeding grounds for the virus, just itching to hop into the next brain. The belief virus goes viral.
The only hope for a cure is early intervention: make sure children develop a robust cognitive immune system, capable of weeding out the diseased beliefs. This means an ability to criticize—rationally evaluate. Education is (partly) health education—strengthening the cognitive immune system. Show videos of people suffering from florid beliefitis (I name no names) and ask if the students want to end up like that. Warn people about the prevalence of the disease. Insist on protective measures. Above all, medicalize the problem—treat it as the disease that it is.  Of course, it is necessary to have sound diagnostic methods, but that is not the insurmountable problem that some people imagine. You just need a qualified epistemologist to advise. Set up a panel of experts, get some funding, and take the problem seriously. We have to stamp out this scourge.
 This history of medicine is progressive medicalization, particularly with respect to the mind. It is only recently that mental disease was recognized as such. This is not a matter of trying to fit psychological disorders into a pre-existing medical framework in a reductive manner; rather, it is expanding medicine to include maladies of the mind. It is past time that we accepted that the belief system can be as diseased as any system of the body. After all, belief is a biological phenomenon and should be treated as such.