Griffiths and Wilkins on Evolutionary Debunking Arguments (Part Two)

Would anyone trust in the convictions of a monkey's mind?

(Part One)

This post is the second in a brief series on the paper "When do Evolutionary Explanations of Belief Debunk Belief?" by Paul Griffiths and John Wilkins (GW - again, apologies for the abbreviation). In this paper, GW argue that it is possible to respond to evolutionary debunking arguments (of the sort covered here) by constructing a Milvian Bridge, i.e. showing how truth-tracking can be complementary to evolutionary success.

In the previous entry, I outlined the basic elements of GW's argument. The last thing I discussed was their claim that our commonsense beliefs are not debunked by evolutionary explanations. In other words, their claim that a Milvian Bridge can be constructed to cover commonsense beliefs. The key question now is how much further can the Milvian Bridge be extended. GW argue that it can be extended to cover scientific beliefs, but not ethical or religious beliefs.

Although I agree with GW about scientific and ethical beliefs, I am not entirely convinced by their support for the evolutionary debunking of religious beliefs. My contention is that the argument they offer in defence of scientific beliefs could easily be co-opted by the defender of religious beliefs. Whether I am right in this depends heavily on whether I am correct in my interpretation of the argument they offer in support of scientific beliefs, so I turn to that first.

(Note: I am not going to cover GW's discussion of ethical beliefs since I have covered that topic at length before)


1. From Commonsense to Science 
As noted last time, although we can be reasonably confident that our cognitive mechanisms do not fundamentally mislead us about the nature of the objects and entities with which we interact on a daily basis, the kinds of beliefs we have about such objects have no ultimate ontological significance. This is in stark contrast to scientific beliefs about the nature of such objects and entities (and more besides) which, while maybe not representative of the ultimate truth, are thought to get us a good deal closer to the ultimate level.

How can these scientific beliefs be justified? Surely, even if the proponent of the evolutionary debunking argument accepted GW's point about commonsense beliefs, they could still maintain that scientific beliefs are debunked. Scientific beliefs, they will say, take us beyond the realm of commonsense, and while it may be true that our cognitive mechanisms have evolved to track the truth within the realm of commonsense, this gives us no ground for thinking that those same cognitive mechanisms can extend us beyond that realm.

GW offer two points that count against the debunker's arguments in this regard. The first seems slightly weak, and I don't think GW mean for it to count for much, but I'll mention it anyway. It is that scientific beliefs, unlike the kinds of commonsense or intuitive beliefs that may have some evolutionary salience, are not the product of one organism's innate cognitive mechanisms. Scientific beliefs are cognitive innovations, built upon the shoulders of giants, and spread by cultural diffusion.

I take it that while the possibility of cognitive innovations being spread through cultural diffusion has some significance, it doesn't really count against the debunker's arguments. Why not? Because there are many beliefs spread by cultural diffusion but that might be thought to lack the status of knowledge. Indeed, religious beliefs may be a classic example of this.

GW's second point is rather more interesting and significant. It is that we can be confident in the content of our scientific beliefs because they are arrived at via a method that is itself justified by commonsense standards. GW refer to this as an indirect, as opposed to a direct, Milvian Bridge. I think their argument has a certain amount of appeal. Speaking for myself, I can certainly say that when I first learned about double-blind testing it seemed like an obviously correct process for removing biased or distorted interpretations of experimental results.

Since I think this point has significant ramifications, I want to try to sketch out their reasoning in slightly more formal terms. I call this the "indirect Milvian Bridge argument":

• (1) Our commonsense beliefs are warranted due to the fact that they are produced by cognitive mechanisms that have evolved to track the truth within the commonsense realm (premise, from previous argumentation).

• (2) If a set of beliefs X is likely to be warranted, and a set of beliefs Y can be derived using standards set by X, then Y is also likely to be warranted (indirect Milvian bridge principle).

• (3) Scientific beliefs can be derived using standards set by commonsense beliefs.

• (4) Therefore, scientific beliefs are likely to be warranted.

I hope this is an accurate reflection of GW's argument. Note that the content of scientific beliefs need not be consistent with commonsense, all that matters is that the method used to derive those beliefs is consistent with commonsense. Indeed, scientific beliefs are quite often counter-intuitive.

2. Debunking Religious Beliefs

As noted in the intro, I'm going to skip over GW's discussion of ethical beliefs. One point worth noting is that GW endorse the view held by Street and Kahane that a possible response to evolutionary debunking arguments in ethics is to reject realist conceptions of ethical truth. This endorsement is significant because GW query at the end of their article whether a similar strategy might be available to the religious believer. But I'll leave this issue to the side in order to focus solely on their argument that religious beliefs are debunked by evolutionary explanations.

GW support this argument by reference to some of the leading theories on the evolutionary origin of religious beliefs. Broadly speaking, there are two main categories of such theories (i) those that maintain that religious beliefs confer some sort of evolutionary benefit; and (ii) those that maintain that religious beliefs are a by-product of other cognitive mechanisms that conferred some kind of evolutionary benefit. There might also be a third category that combines both of these approaches (i.e. first a by-product, then an adaptation).

An example of a theory belonging to the first category is that of David Sloan Wilson. He argues that religious belief was selected for due to its potential to enhance social cohesion and prosocial behaviour. Examples of theories belonging to the second category would be those of Barrett, Boyer and Atran. They argue, for instance, that belief in a divine agent is a by-product of a cognitive mechanism for detecting agency (sometimes called the "hyper-active agency detection device" or HADD).

GW argue that neither of these theories can be used to support the existence of a Milvian Bridge for religious belief. Why not? Because in neither case is there any suggestion that religious beliefs were the product of truth-tracking processes. In Wilson's case, the beliefs are selected for their social benefits, not for their ability to track the mind-independent truth. In the case of by-product theories, the beliefs are produced by a mechanism with a propensity for making type 1 (false positive) errors.

3. An Objection

Although I am certainly inclined towards their conclusion, I think GW's argument against religious beliefs is a little too quick. In particular, I worry about their dismissal of by-product theories. They seem to accept, too readily, that beliefs in the existence of a divine mind will be the result of a type 1 error by the relevant cognitive mechanism.

Given my earlier formulation of the indirect Milvian bridge argument, it will probably come as no surprise to learn that this forms the backbone of my objection. I'm inclined to ask: If we are allowed to build an indirect bridge from the realm of commonsense to the realm of science, then why can't we build a similar bridge from the realm of commonsense to the realm of the divine? Here's what I have in mind.

First, I presume our beliefs about the existence of other agents are not massively erroneous (i.e. that, even though the rate of type 1 errors might be high, our HADD still picks out real agents more often than not), I do so on the grounds that, following GW's earlier arguments, other agents are part of our commonsense realm and our beliefs in this realm are likely to be truth-tracking.

Given these presumptions, I think it is plausible that our method for identifying agents in the commonsense realm could (maybe using other criteria set by our commonsense beliefs) be used to derive beliefs about the existence of other minds, including the divine mind. To quote Griffiths and Wilkins talking about scientific beliefs:

"If evolution does not undermine our trust in our cognitive faculties, neither should it undermine our trust in our ability to use those faculties to debug themselves - to identify their own limitations, as in perceptual illusions or common errors in intuitive reasoning."

Quite so, but why assume that we can't debug the HADD and still arrive at a belief in the existence of a divine mind? 

I suspect there are two types of response that GW might make to this. 

First, they could argue that they already acknowledge this possibility since they accept (at the very end of their article) that debunking is not disproving and that other reasons could be adduced in support of religious belief. I think that's right, but then I'm forced to wonder why we need the kind of argument that GW offer in support of scientific beliefs. Surely the concern of the debunker in both cases is with the possibility of justifiably moving beyond the commonsense realm; and surely the response, in both cases, is that an indirect Milvian bridge can be built? 

Second, they could argue that the problem with the HADD is that it is, contrary to my presumption, massively erroneous. That might be true too, but then I can't see why this wouldn't undermine their argument in defence of our commonsense beliefs. Surely other agents are part of our commonsense realm, and surely our cognitive mechanisms would have evolved to track the truth about such entities?

Okay, that's all I have to say on this for now. Hopefully, John or Paul might pop-up in the comments and offer some critique of what I've said. 

[Addendum: I'd like to add that I just came across this paper which seems to address the religious belief issue at considerable length.]