Dawkinsists insist upon the irrationality of all religious thoughts (seemingly oblivious to the cogency of McGrath’s, for example), and even I would oppose rationality and postmodernity—but what is the sense of such statements? What do we mean by ‘rational,’ in such contexts? Surely not just that we agree with our communicants’ presumptions (although we might legitimately use the word that way), so presumably rationality has something to do with our beliefs being coherent (with each other) and proportionate (with all the evidence).
......Unfortunately our beliefs arise from inherently catastrophic processes. Each of us must interpret empirical data according to an existing system of beliefs (if we are being rational) and yet that system might be modified catastrophically (in the mathematical sense, even whilst we are rational) in the light of the new evidence. Such processes may occur (in a very obvious way) even within science, when scientific paradigms change, but surely they must be occuring within each of us much of the time (if we are not fixated, rather irrationally, upon the first system of beliefs that we acquired).
......Consider the checkerboard illusion. Naturally we first see that A is darker than B. We then discover that A is actually the same shade as B but even so, when we look at the checkerboard again we still see that A looks darker than B. We may now think “that A looks darker than B,” instead of “that A is darker than B,” but at the moment of looking we surely form, if only very briefly, the belief that A is darker than B, and we are not then being irrational, it is just that thinking takes time—even rational belief revision takes time. And of course, the relationship between the bulk of our beliefs and reality is rather more complicated than in that simple example, whence the actual coherence and proportionality of our beliefs would seem to be more of an ideal than a possibility.
......The problem is that, for our beliefs to be proportionate, they should depend upon how the world is, so we are rather at the world's mercy when it comes to being rational (we are not to prejudge matters too much since rationality, no less than postmodernity, is opposed to prejudice). So I fear that my use of ‘irrational,’ when describing Postmodernism for example, may be little more than hypocritical rhetoric—hypocritical because I find myself unable to say what precisely I mean, in such contexts, by ‘rational.’ As I’m about to embark on a PhD in (analytic) Philosophy, I clearly need to understand what we (at least) mean by ‘rational,’ and ‘logical,’ and so forth, and so I’d be interested in what others take such words to mean...
......Can you imagine, for example, Dawkins being abducted by aliens, real aliens? (If not then change this example:) Given such quantities of first-hand experiences (which would not amount to scientific evidence of course, since such empirical data would be too private), Dawkins might change his beliefs about UFOs. But of course, had another man come to him earlier with such a story, Dawkins would surely have told him to consider seriously the probability that he had imagined the abduction. So when Dawkins returns to Earth, and as that empirical data turns into memories of a rather strange character (amongst his ordinary ones), Dawkins might naturally (and not unreasonably) revert to his sceptical beliefs. His friends would no doubt be pleased by his (apparent) return to sanity.
......But now suppose that the Pope was somehow shown all the primary data (and presented with all the reasoning) that atheists (who we may suppose, for the sake of this example, are right) find so important. He might lose his faith, at least temporarily. But now, when the Pope similarly reverts to his earlier beliefs (and regards that primary data as, perhaps, the work of the devil), would Dawkins say that that was reasonable? He might not; and indeed, for a Dawkinsist to regard the former but not the latter as rational would be one legitimate use of the word ‘rational.’ But we are associating rationality with objectivity (and even the Pope presumably hopes for coherent beliefs).
......And we are associating rationality with the proper weighing-up of all the available evidence—such as we might imagine both Dawkins and the Pope were attempting, at key moments within those fictions. Being rational involves choosing between one set of beliefs (with their explanation of the data) and another set (with their explanation), so it hardly stands opposed to being in two minds about things, from time to time. And whilst those two examples are naturally rather odd, that was just to keep them simple. People who try to think things through (and especially analytic philosophers, who positively seek out problematic cases) will often find themselves in analogous situations, often with little rational expectation of making up their minds any time soon. But in various situations, one set of beliefs might be more appropriate.
......Let S = “That spatula was made on another planet,” in the first example, and “That statue did not cry real tears” in the second, and let X = Dawkins, and the Pope respectively. Then X will end up with a lot of evidence of one kind for S, and a lot of evidence of another kind for not-S. (Incidentally the checkerboard illusion illustrates those two kinds, and for an example of further complications consider the St. Petersburg paradox:) So, it is easy to see that the weight that X ought to give to each sort of evidence (as X thinks rationally about the world) is a function of X’s involvement with the world—whence there could even be times when the evidential bases (for the two belief sub-systems) are incommensurable (this post defends my previous post:)