I find it curious that Blackburn, who sets about taking about the theory of rational choice, so shuns the word rational (ostensibly because it confuses endlessly.) But regardless …
Eligible persons, that is “anyone with consistent, transitive preferences over a set of options,” make decisions on the basis of two concepts: (a) util, a function of expected utility where utility is valued on the basis of transitivity, and (b) revpref, which is the preference relation of any choice to other available options in that particular situation. And so Blackburn builds a very robust theory of rational choice that can "interpret the decision of any eligible agent as if they were seeking to maximize expected utility.” (164)
I find Blackburn’s approach problematic still. It reminds me of the inner-consistency accounts of rationality that we’d talked about last seminar. The crank-oil example, which seems intuitively irrational, would not be classed as so by Blackburn’s system. I'd thought that this was inherently problematic because I’d felt that theories of rational choice surely must be able to make normative claims and make recommendations but Blackburn denies this again, and again (136, 167). But perhaps Blackburn has a point, that it may be an inherent limitation of theories of rationality that they cannot adjudicate on the primacy of one preference set over another. Maybe that’s where ethics gets to feature.
XY: I suspect that he eschews "rational" for the same reason that Smith does. He has a notion of the reasonable, but what others mean by "rational" he finds implausible. Your summary of his Util/Revpref theory is nice, but I'm not sure what you mean in calling it a robust theory. Isn't his point that it is not normative and not predictive? In short, isn't his point that it is like the present aim or inner consistency theory, in that it can accommodate (almost) any set of choices as "rational"? In fact, isn't that why he offers Revconc as an alternative? This will be fun to talk about in seminar!
ReplyDeleteBlackburn says that "utility itself" can be used as a construct "from mathematically tractable ways of handling" the concerns of eligible agents (162). We see where individuals' utilities lie by their concerns which are exposed through their choices. This is one of his main concerns, not a normative theory of rationality. In fact, he consistently distances himself from the idea of a normative theory of rationality (much to Nico's pleasure I've marked them) "because it perpetuates the illusion that we are talking about a special sorts of person" when all individuals are eligible so long as they can be interpreted in terms of utilities (shown through preference and choice) (164).
ReplyDelete