Delusions and Verisimilitude

What's the one thing everyone knows about delusions? That they're false beliefs. Not so fast. Already we have two problems. First, there is much debate among philosophers about whether they are really beliefs (recently the linguist Dariusz Galasinski has written a fascinating post about whether delusional utterances even always have to be propositional statements).

Additionally, it's not clear that delusions always have to be false. An oft repeated sentiment in psychiatry is that even a true belief ("my wife is cheating on me") could be delusional if held with the right (or, I suppose, wrong) sort of conviction. That idea is usually attributed to Karl Jaspers, but not having read him yet I can't confirm. I have also seen it attributed to Lacan, but I don't recall coming across it when I read his weird, poetic Seminar on the Psychoses. Perhaps someone could point me to the source.

I am intrigued by the possibility that a true statement could be a delusion. It seems superficially rather a contradiction in terms, after all "delusional" is a rhetorical way of describing something as patently false. Nonetheless it makes some sense. It seems possible to have a pathological conviction about something true. Imagine correctly insisting that it was raining outside when you had no means of knowing it were so. Healthy assertion about most things contains withing itself the germ of the possibility that the person asserting could be wrong.

It seems then that we can be delusionally correct in certain circumstances. Is there also another way delusions could be true? Could they be, as I think some therapists would like to suggest, a form of communication about reality? Could it be that delusions, even quite wild ones ("I am having my mind read by the president"), have some element of truth to them?

Some people think so. For example, one therapeutic approach suggests finding the relate-able component of any delusional utterance and focusing on that. A supervisor recently told me that she was once confronted by a patient yelling "we're at war!" and responded by saying "you must be very frightened". I can't resist the detail that the patient turned out to be flatly correct (it was 2003 and she was referring to the outbreak of the Iraq war), but my supervisor's approach was a good one I think. When someone says something to you that is on-the-face-of-it at odds with your understanding of reality, it seems more communicatively cooperative to find the part that both of you make sense of. "You think other people can read your mind? Well that must feel terrifying and very exposing."

Such an approach sometimes gets packaged up as a form of relativism or pluralism, the idea being that there is no such thing as one truth. That might feel quite comfortable for people of a certain philosophical persuasion; if you are a pluralist or post-modernist about truth, then you needn't be troubled by the idea that any given statement is false.

Do we have to have different truths?

Unfortunately I like the therapeutic stance but not the philosophical posture. I have come to belief in truth. By this I just mean that I think that some states of affairs are the case, while others are not. What is more, I think most people secretly agree. If you jump off a bridge (all other things being equal), you'll end up moving downwards. If there were nothing that were true it would be supremely weird that we managed as a species to agree over so many things.

So what do we do? Can we still say, following sympathetic therapists, that delusions have some truth to them? I think we can. Beyond the idea that some statements are true and others false, there is the idea in philosophy of science, that any given statement can be more or less true; that is, have more or less verisimilitude. Take these two statements: 1. "There is no such thing as schizophrenia" 2. "Schizophrenia is a real illness". They seem mutually contradictory, as though they couldn't both be true. They certainly cause a lot of argument. Regular readers of this blog might already have a view about which is right and which is wrong.

I think such arguments usually arise because the people apt to make one of those statements often think they are saying something that could be simply true or false. This is a mistake. One of the reasons such contradictory statements can exist (and it is surely one of the reasons that relativism about truth is such a respectable position in some circles) is that so many of the claims made in this domain are impossibly under-specified as truth-assertions. That is to say, my example statements 1 and 2 use such loosely understood words ("schizophrenia", "real") that we cannot gauge their truth value without interrogating some hypothetical speaker to get further qualification.  For what it's worth I think both statements have some verisimilitude. I go back and forth about which one I think has more truth than the other, but they are both getting at something basically correct.

How does all this help us with delusions? Delusions are like the statements studied by philosophers of science. They are often (though not always) statements about how the world is. If this were not so we might not bother calling them delusions to begin with. People falsely claim they are being watched; that they are of unusually superior ability; that they are infected with some fatal disease. It seems right to be aware that such beliefs are are often untrue. At least the headline assertion is often false. However delusions are usually complex and under-specified statements. Minimally, a person who makes an outlandish claim about the world is also making a less ridiculous one about what it is like to be them at that moment. Broadening our view somewhat, they might be making a quasi metaphorical statement about some aspect of their environment. I will not be saying anything radically new if I suggest that sometimes, delusions are informative in surprising ways.

Therapeutically this is nothing new. Sympathetic listeners have long held that delusions contain something true. Confronted with an uncomfortable contradiction between a patient's beliefs and their own, many people's instinct seems to be to assert the possibility of a plurality of truths. People of some philosophical persuasions (self included) find this too wishy-washy. Perhaps verisimilitude can help us square the circle.