The ecological rationality of the bad old fallacies

by velisar 2 min read19th Mar 201413 comments


I think that the community here may have some of the most qualified people to judge a new frame of studying the fallacies of argumentation with some instruments that psychologists use. I and my friend Dan Ungureanu, a linguist at Charles University in Prague could use some help!

I’ll write a brief introduction on the state of argumentation theory first, for context:

There is such thing as a modern argumentation theory. It can be traced back to the fifties when Perelman and Olbrechts-Tyteca published their New Rhetoric and Toulmin published his The uses of argument. The fallacies of argumentation, now somewhat popular in the folk argumentation culture, have had their turning point when the book Fallacies (Hamblin, 1970) argued that most fallacies are not fallacies at all, they are most of the time the reasonable option. Since then some argumentation schools have taken Hamblin’s challenge and tried to come up with a theory of fallacies. Of them, the Informal logic school and the pragma-dialectics are the most well-known. They even have made empirical experiments to verify their philosophies.

Another normative approach, resumed here by Kaj Sotala in Fallacies as weak Bayesian evidence, is comparing fallacious arguments with the Bayesian norm (Hahn & Oaksford, 2007; also eg. Harris, Hsu & Madsen, 2012; Oaksford & Hahn, 2013).

We cherry-pick a discourse to spot the fallacies. We realized that a couple of years ago when we had to teach the informal fallacies to journalism masters students: we would pick a text that we disagree with, and then search for fallacies. Me and Dan, we often come up with different ones for the same paragraph. They are vague. Than we switched to cognitive biases, as possible explanations for some fallacies, but we were still in the ‘privileging the hypothesis territory’, I would say now, with the benefit of hindsight.

Maybe the world heuristic has already sprung to some of you. I’ve seen this here and somewhere else on the net: fallacies as heuristics. Argumentation theorists only stumbled on this idea recently (Walton, 2010).

Now here’s what this whole intro was for: lesswrong and before overcoming bias are sites build on the idea that we can improve our rationality by doing some things in relation to the now famous Heuristics&Biases program. The heuristics as defined by Twersky and Kahneman are only marginally useful for assessing the heuristic value of a type of argument that we use to call a fallacy. The heuristic elicitation design is maybe a first step: we can see if we have some form of attribute substitution (we always have, if we think that a Bayesian daemon is the benchmark).

We started with the observation that if people generally fall back to some particular activity when they are “lazy”, that activity could be a precious hint about human nature. We believe that it is far easier to spot the fallacy a) when you are looking for it and b) that you are looking for it usually if the topic is interesting, complex, grey: theology, law, politics, health and the like. If indeed the fallacies of argumentation are stable and universal behaviors across (at least some) historical time and across cultures, we can see those “fallacies” as rules of thumb that use other, lower-level fast and frugal heuristics as solid inference rules in the right ecology. Ecological rationality is a match between the environment and the – bounded rational – agent’s decision mechanisms (G. Gigerenzer 1999, V. Smith, 2003).

You can’t just invent a norm and then compare behaviors of organisms or artifacts with it. Not even Bayes rule: the decision of some organisms will have to be Bayesian only in their natural environment (E.T. Jaynes observed this). That is why we need a computational theory of people even when we study arguments: there is no psychology which isn’t evolutionary psychology. We need to know the function, but saying fallacy is about valence, so people traditionally ask why we are so narrow or stupid or, recently, when are the fallacies irrational and when they are not. (no, we don’t want to start again the 1996 polemic between Gigerenzer and Tversky&Kahneman!).

Well, that is what we think, anyway. And if you spot a big flaw, please point it to us before we send our paper to a journal.

Here’s the draft of our paper: