Wednesday, June 27, 2018

On Desire 2018. Part 52: Railton's Beliefs

There is an element of Peter Railton’s theory of desires that concerns me. Like Gregory, Railton (and this is my interpretation) handles certain objections to his theory of desires by removing key desires - hunger, thirst, sex, pain - from the set of desires. As such, his theory of desires is actually a theory of “something else” - something quite different from desires.

Railton, Peter, (2017), “Learning as an Inherent Dynamic of Belief and Desire,” In Deonna J. & Lauria F. (eds). The Nature of Desire. Oxford University Press.

Alex Gregory made a similar claim in the previous article.

Gregory, Alex, (2017), “Might Desires Be Beliefs about Normative Reasons for Action?” In Deonna J. & Lauria F. (eds). The Nature of Desire. Oxford University Press.

Whereas Gregory seems to be providing a theory of beliefs, desires-as-means, and “drives”, Railton seeks to distinguish between beliefs, malleable desires, and drives.

An important part of Railton’s theory is that desires are like beliefs in that desires can be learned. That is to say, through experience, desires change. However, we need to answer the question of what this “change through experience” implies. Railton wants to compare this to updating beliefs by “encountering” evidence. I do not think it is correct. Rather, it is more like changing one’s weight by encountering a large quantity of chocolate cake. The fact that something changes does not imply that it is seeking to match some independent truth.

This corresponds to what I have said is a distinguishing characteristic between beliefs and desires. A single belief can be wrong - it can be in need of being corrected. A single desire can be in need of being corrected if it does not correspond to the world. A single desire cannot be mistaken. It can only be in conflict with another desire. Railton wants to conceive of changes as potential corrections.

That is the overall view. I need to get into specifics.

With respect to belief, Railton’s thesis is:

(Bel p) A belief that p is a compound state consisting in (1) a degree of confidence or trust in a representation, p, that (2) gives rise to and regulates a degree of expectation that things are or will be as p portrays them, and (3) this degree of confidence or trust is disposed to strengthen or weaken in response to the extent to which this expectation that p is met or violated in subsequent experience.

The important point that Railton wants to make is that “confidence” is a sentiment - a feeling - attached to a proposition. Furthermore, the nature of this sentiment - it’s strength - is altered by interaction with the environment. Specifically, interaction with evidence or counter-evidence strengthens or weakens that belief.

He is going to relate this feature - being a sentiment altered through experience - to what is true of desires to show that desires are like beliefs. Desires, after all, are also sentiments that can be altered through experience. I will get to this in my next post.

While the focus is still on beliefs, I want to draw attention to what I have called the defining characteristic of belief insofar as belief is distinct from desire. A belief, by itself, can be incorrect. A desire, by itself, cannot. A desire can only be in conflict with another desire.

There is nothing in Railton’s statements about belief that denies this feature. The sentiment that measures the certainty of belief is a sentiment that measures the agent’s confidence that a belief, by itself, matches the world. It may be a sentiment that can change as a result of interaction with the world, but that change is still a measure of the confidence (or lack of confidence) in whether the world is as it is believed to be.

Now, this is supposed to be a series on desire, not on belief. So, let’s look at what Railton says about desire and how this view of belief is relevant.

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