Mercier and Sperber on the origins of reasoning

If I had to bring only one journal to a desert island, it would probably be Behavioral and Brain Sciences; I am continuously amazed by the high-quality and innovative nature of its contents. It works with the very interesting format of one target article per issue (usually a long, controversial and ambitious piece), and short commentaries by peers. One of the signs that it is a truly exciting journal is that commentators often come from different disciplines; in particular, it is very common to see philosophers commenting. The current issue, for example, is dedicated to Sue Carey’s new book The Origin of Concepts, and has commentaries by people such as Tyler Burge, Christopher Gauker, Edouard Machery, Eric Margolis (just to mention some of the philosophers).

But today I would like to focus on the April issue of BBS, with a controversial target article by Hugo Mercier and Dan Sperber: ‘Why do humans reason? Arguments for an argumentative theory’ (an open-source pdf of the paper can be found here). Let me quote its abstract in full:

Reasoning is generally seen as a means to improve knowledge and make better decisions. However, much evidence shows that reasoning often leads to epistemic distortions and poor decisions. This suggests that the function of reasoning should be rethought. Our hypothesis is that the function of reasoning is argumentative. It is to devise and evaluate arguments intended to persuade. Reasoning so conceived is adaptive given the exceptional dependence of humans on communication and their vulnerability to misinformation. A wide range of evidence in the psychology of reasoning and decision making can be reinterpreted and better explained in the light of this hypothesis. Poor performance in standard reasoning tasks is explained by the lack of argumentative context. When the same problems are placed in a proper argumentative setting, people turn out to be skilled arguers. Skilled arguers, however, are not after the truth but after arguments supporting their views. This explains the notorious confirmation bias. This bias is apparent not only when people are actually arguing but also when they are reasoning proactively from the perspective of having to defend their opinions. Reasoning so motivated can distort evaluations and attitudes and allow erroneous beliefs to persist. Proactively used reasoning also favors decisions that are easy to justify but not necessarily better. In all these instances traditionally described as failures or flaws, reasoning does exactly what can be expected of an argumentative device: Look for arguments that support a given conclusion, and, ceteris paribus, favor conclusions for which arguments can be found.

The paper has provoked heated reactions, and has even had some media exposure (here is a NYT article on it). I had read a pre-print version of the paper last year, but unfortunately by then it was already too late to send a commentary proposal. I’ll probably write a proper rejoinder at some point, but for now let me present some of my incipient thoughts. (Let me add that I have not yet had the chance to read the commentaries, and I anticipate that much of what I will say now is also articulated in some of them.)

First, the points of agreement. Mercier and Sperber’s contribution is extremely important in that it emphasizes the crucial role of argumentation and dialogical practices for the development of human thinking and reasoning. With respect to logic in particular, but with respect to reasoning more generally, we’ve been much too focused on the individual dimension of the lone thinker, unduly disregarding the inherently social nature of much of our cognitive processes. In a forthcoming commentary to an article by S. Elqayam and J. Evans in BBS (this time I was not too late!), I attempt to retrace the historical and philosophical origins of the idea that reasoning and logic pertain predominantly to mono-agent situations of internal thinking processes. In a nutshell, for most of its historical existence, logic was thought to be the art or science of debating/disputing/arguing (thus pertaining to public, multi-agent situations), and it is only in the modern era (with Descartes and in particular Kant) that it was internalized, so to speak, and became seen as pertaining to private, mono-agent situations. A significant part of my new research project to be commenced in July will concern precisely a reconceptualization of logic and deduction in terms of their dialogical (historical and conceptual) origins. (I have talked a bit about it before here.)

So, from that point of view, I am thrilled to see emphasis placed on the social level to explain the development of human reasoning, an aspect which is absent in most conceptions of reasoning available (e.g. Piaget’s). For me, it has to be an externalist/extended cognition story, in which external, public (often social) experiences then become internalized and thus shape much of our cognitive processes (Clark has a similar take on the influence of language on thinking, developed in Chap. 3 of Supersizing the Mind). But it seems to me that Mercier and Sperber went too far in the opposite direction in their reaction to mono-agent, private conceptions of reasoning (perhaps following the usual Hegelian-Marxist process of the swinging pendulum). I concur that much of our reasoning is shaped by the social experiences of argumentation, but it seems exaggerated to claim that these experiences are all that reasoning is about (originally). Of course, it may well be a merely verbal disagreement, i.e. what we mean by ‘reasoning’ in the first place, but I’m reading Mercier and Sperber as making the bold claim that all thinking processes ultimately originate from practices of argumentation. Anyway, here are my main arguments against their theory:

1. It reduces reasoning to inherently social experiences. As I said, I am in total agreement that a significant portion of our thinking/reasoning originates from social experiences, which is only natural given that we are such social animals. But it seems too strong to claim that there is no influence on reasoning processes from the non-social interactions of the agent with her environment (on an externalist approach), or simply by the internal development of her reasoning capacities (on an internalist approach).
2. It reduces reasoning to inherently linguistic experiences. I’ve had this worry for a long time regarding Brandom’s inferentialist program based on the ‘game of giving and asking for reasons’, and Mercier and Sperber seem to take a similar position. Crucially, it implies that pre- or non-linguistic creatures fall outside the scope of rationality and reasoning. But language is relatively a late-comer in the evolution of the human species, and it is implausible that selection for reasoning would have started only once language was already present.
3. It fails to appreciate the strong presence of cooperative forms of dialogical interaction. One fruitful taxonomy of dialogical situations, proposed by K. Stenning in Chap. 5 of Seeing Reason (btw, Stenning is my favorite researcher in the field of psychology of reasoning; big fan of David Over too) is between adversarial and cooperative dialogical interactions. My own reconceptualization of deduction in terms of its dialogical origins emphasizes (as does Stenning) its adversarial nature. Much of the ‘surprising’ results observed in experiments with deductive reasoning tasks might be explained in terms of the subjects engaging in the ‘wrong’ game; they take the task to be some sort of cooperative task, while in fact it is adversarial in essence. My feeling is that, overall, our dialogical practices are much more often cooperative than adversarial (naturally, a claim that could and should be tested empirically), and even insofar as reasoning in general is shaped by dialogical interactions, Mercier and Sperber’s model only seems to accommodate the adversarial component. My claim concerning the dialogical origins of deduction is very different in that it makes no appeals to evolutionary considerations (deductive reasoning is for me a cultural development), and in that it attributes a role to adversarial dialogues in the emergence of deductive reasoning, not reasoning in general.

There is much more that I could (and will, at some point) say on this highly stimulating paper, in particular concerning how the authors interpret the data on confirmation bias (my favorite reasoning bias as well, but I strongly disagree with their take on it), but this is already too long for a blog post.

(I do realize that a lot of my posts are on the ‘origins of X’, with different instantiations of X, but this simply reflects the fact that this is the kind of philosophy I am most interested in: going back to the roots, the origins, of a given concept/phenomenon. You can call it ‘roots philosophy’, if you want!)

 UPDATE: Massimo Pigliucci bashes the paper. I agree with many of the points he makes, in particular with the overall rejection of evolutionary psychology. In this case in particular, it is yet again a ultra-adaptationist story, but clearly reasoning may well be a byproduct of some other adaptive feature(s). Moreover, it is far from obvious that the capacity to 'win arguments' would really give individuals the evolutionary edge so as to be selected for.