Saturday, 13 March 2010

Criticisms of M-rationalism

In my previous post, I adumbrated the Motivational Rationalist (henceforth, M-rationalist) objection to my claim that one may instantiate a rational transition even if one lacked the concept of a rational transition. In the present post, I will limn a few criticisms of M-rationalism. Specifically, I will argue that M-rationalism can preserve our quotidian intuitions—e.g., entail that most of the transitions we would ordinarily take to be rational are rational—only if it is able to accommodate the possibility that many (if not most) of the inferences we would putatively regard as rational are not motivated by a belief to that end. But this does not seem to be a condition that M-rationalism can fulfil. To see why this is so, consider the following example:

The Unreflective Inference Example:
Mark is talking on the phone and is informed by his girlfriend, Jessica, that she will be arriving at 7:30pm that evening, and that his best friend, Rick, will be arriving a few hours after her. After hanging up the phone, Mark’s roommate asks him if Rick will be getting in before 7:00pm that evening. Without much hesitation Mark says no. I maintain that in the typical case, Mark does not form the belief that the inference he performs accords with the principle of transitivity and, a fortiori, no such belief motivates him to make the inference. In fact, Mark may not have formed any belief that takes as its object the particular (token) inference he performs. When his roommate poses the question the answer may simply come to Mark, without any accompanying beliefs about the inference itself. Presumably, Mark is aware of the content that forms the premises of the inference: the fact that his girlfriend will be arriving after 7:30pm, the fact that his best friend will be arriving after his girlfriend, and the fact that 7:00pm is earlier than 7:30pm. However, I wish to allow that he may have no beliefs about the inferential pattern in which this content features; for example, that the inferential pattern accords with the principle of transitivity or some unspecified rational norm. On this score, I hold that an inference-based belief may be very much like a perception-based belief; neither the inference nor the perceptual experience need feature as the object of some higher-order belief in order for the agent to have a belief based on that inference or perceptual experience.

Whether motivated by the relevant belief or not, I wish to say that Mark’s inference constitutes a rational transition; it provides Mark with a reason for his inference-based belief that Rick will be arriving after 7:00pm. But according to the Token M-rationalist, Mark’s inference is a rational transition only if it is motivated by his belief that it is generalisable. However, it is not immediately clear that Mark has the belief that the particular inferential token accords with a rational principle or, a fortiori, that such a belief motivates Mark to perform the inference. In fact, if one were to ask Mark if his inference was motivated by the belief that it is generalisable, he may very well respond by saying that he had not given the matter any thought. If we were to take such a reply from Mark at face value, we would have to conclude that Mark had not formed the relevant belief and that it was therefore unavailable to motivate his inference. Consequently, the Token M-rationalist would be forced to say that Mark’s inference fails to constitute a rational transition. But this strikes me as highly counterintuitive.

It should be clear that the preceding argument has some force against Token M-rationalism. However, it seems to have less force against Type M-rationalism. If we assume that having the concept of a particular inferential transition entails having the belief that transitions of that type are generalisable, then the fact that Mark has the concept of a transitive inference entails that he has the relevant belief.

However, Type M-rationalism is still saddled with the following two difficulties. First, it significantly narrows the scope of application of Wallace’s distinction between inferences that are motivated by a rational principle and inferences that merely correspond with a rational principle. Presumably, Wallace intended that the distinction be applied on a case by case basis, so that a single agent, Mark, could perform a transitive inference that was rationally motivated on one occasion and then perform a transitive inference that was not rationally motivated on another (future) occasion. However, Type M-rationalism runs into difficulties when it tries to accomodate this aspect of Wallace’s distinction. If we assume that the motivating belief is a standing belief, then it should be available to motivate all of the inferences that Mark performs once he has acquired the concept of a transitive inference.

Moreover, Type M-rationalism simply fails to provide us with the theoretical resources we would need to draw any possible distinction between those cases in which a particular inference is motivated by a standing belief and those occasions when it is not. The upshot is that an agent either has all transitions of a certain type motivated by a standing belief (assuming that the relevant standing belief is present) or she has no transitions of that type motivated by a standing belief (assuming that the relevant standing belief is absent). While this allows for the intelligibility of Wallace’s distinction when it is construed in terms of a contrast between a rational agent (equipped with the relevant concepts) and a non-rational agent, it does not allow for such a distinction with respect to a single rational agent at different times. However, this implication seems to fly in the face of Wallace’s aims in introducing the distinction.

Second, there remains a lacuna in the Type M-rationalist argument. Recall, the Type M-rationalist maintains that any agent may be ascribed a standing belief that a particular transition is generalisable simply in virtue of having the concept of that transition. I am largely sympathetic to this claim. However, the Type M-rationalist wants to make the further claim that the standing belief is what motivates the agent to complete the relevant inference. However, it is not immediately clear that this is so. The Type M-rationalist may have shown that there is a standing belief available, but she has not shown that it motivates the agent to complete the inference. Moreover, it seems that the question of whether or not it is the standing belief that does the motivating is an empirical rather than conceptual question. Once we recognise that it is possible (not only conceptually but also empirically) for a particular inferential pattern to be instantited without the belief that the inferential pattern in generalisable, it becomes an empirical question whether or not that inferential pattern is motivated by such a belief on a given occasion. This represents a significant challenge to Type M-rationalism since it makes the plausibility of the thesis hostage to future scientific investigation. Should future investigation reveal that it is generally the case that our unreflective inferences are not motivated by a standing belief, then Type M-rationalism would entail that such inferences fail to constitute rational transitions.

To recap, I have argued that M-rationalism (in both of its forms) faces a challenge when it comes preserving our ordinary intuitions about which transitions are rational. In the case of Token M-rationalism, the objection is much more straightforward. Although we would ordinarily regard unreflective inferences, like that performed by Mark, to be reason-conferring, Token M-rationalism seems to entail that such inferences are not rational transitions. In the case of Type M-rationalism, whether or not it is able to accommodate cases like that of Mark will depend on future scientific investigation. Should we discover that the inferences of mature humans are motivated by a standing belief that they are generalisable, all is well. But if we were to discover that this is not so, then Type M-rationalism would have the highly counterintuitive consequence that such inferences are not rational transitions.

I believe that it is a weakness for a philosophical theory to have its plausibility be contingent in this way. At best, we are forced to wait until all the facts are in before we can endorse the theory, and at worse, one begins to suspect that this contingency is merely a symptom of a deeper ailment—namely, that the theory fails to capture what is most fundamental about the concepts it sets out to explain.

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