Theism and Explanation - Appeared-to-Blogly

152 Appendix
the impingements upon it, and use your knowledge of the laws of physics
to predict the outcome for any event.” 25 The second is the design stance:
here “one ignores the actual . . . details of the physical constitution of an
object, and, on the assumption that it has a certain design, predicts that it
will behave as it is designed to behave under various circumstances.” 26 It is
the third strategy that is the focus of Dennett’s attention, namely the intentional
stance. When adopting this strategy, we treat the system in whose
behaviour we are interested as a rational agent, and by attributing to it
certain beliefs and desires, we predict how it ought to behave.
What beliefs and desires do we attribute to the system in question, in
order to arrive at our prediction? And what does it mean to treat something
as a rational agent? Dennett’s answer is admirably concise.
(1) A system’s beliefs are those it ought to have, given its perceptual
capacities, its epistemic needs, and its biography. . . .
(2) A system’s needs are those it ought to have, given its biological needs
and the most practicable means of satisfying them. . . .
(3) A system’s behavior will consist of those acts that it would be rational
for an agent with those beliefs and desires to perform. 27
The fi rst two of Dennett’s points are relatively uncontroversial, provided
we understand that the “ought” here has no moral connotations. It means
simply that we attribute to the subject the beliefs and desires (or beliefs and
pro attitudes) that we would expect her to have, given the kind of being she
is and her particular history. The third requirement, namely that we treat
the subject as a rational agent, is more controversial. But it is, I want to
argue, at the heart of such explanations.
This rationality principle is also central to the work of Donald Davidson,
in whose writings it is sometimes referred to as “the principle of charity.”
At times, Davidson seems to offer a particularly strong version. When
discussing, for instance, the impossibility of incommensurable conceptual
schemes, Davidson argues that in order to understand other people “we
must count them right in most matters.” 28 But he offers what is apparently
a weaker version of the principle when discussing intentional explanations.
In this context, Davidson argues, the principle of charity demands that
we fi nd “a large degree of rationality and consistency” in the behaviour of
those whose actions we are explaining. 29 For Davidson, this presumption of
rationality is not something imported from outside as it were; it is implicit
in the very concepts we use to explain behaviour intentionally. 30 In other
words, without the rationality principle (or principle of charity), there can
be no intentional explanations.
Why do we employ such a principle? One answer would be, “because it
works.” If we treat people as if they were rational agents we can often understand
and even predict their behaviour. Dennett, for one, seems tempted by
this instrumentalist view, arguing at one point that the rationality which