Theism and Explanation - Appeared-to-Blogly

74 Theism and Explanation
(1) There exists a rational agent A with intended goal G.
(2) A has beliefs B 1 , B 2 , . . . B n relating to the attainment of G.
(3) If B 1 , B 2 , . . . B n were true, E would be the best way of achieving G.
(4) Rational agents always choose the best way of achieving their goals.
(5) Therefore A will do E.
The key premises to note are (3) and (4). The objection levelled by Smith
and Pennock assumes that our explanation is nomological, that it cites laws
connecting the agent’s observed behaviour with some a particular set of
beliefs and desires. But whether or not such laws exist (Appendix 3.3.1), an
explanation of this form does not rely on them. What it relies on is a rationality
principle (5.2 and Appendix 1.3). It predicts an agent’s behaviour by
assuming that she will act in a way that is consistent with her beliefs and
desires in order to achieve her goal (5.2–5.3).
In other words, the objection put forward by both Smith and Pennock
assumes a false dichotomy. It assumes that the world is either governed by
natural laws or it is the product of a mere “whim” on the part of a supernatural
agent. But these are not the only options. The world could, conceivably,
be the work of a supernatural agent acting rationally in order to
achieve his goals. If we posit a particular goal, we might be able to predict
his behaviour. The fact that this agent is capable of working miracles is neither
here nor there. The key question is: What would be the most rational
way for such an agent to act in order to achieve this goal? The answer may
or may not include miracles. 53
4.4.4 Hume’s Argument
What if we did decide that the most rational way for God to act, in these
circumstances, was by way of a miracle? Then a miracle is what we would
expect to observe, given the theistic hypothesis. But the atheist might simply
refuse to recognise any alleged miracle as a miracle. He might, in support
of this refusal, appeal to David Hume’s argument, that it is always
more probable that a miracle report should be false than that a miracle has
occurred. If Hume is right, then we would never be in a position to verify
this particular theistic prediction. We would never be justifi ed in regarding
any observed fact as a miracle. 54 If this is correct, then at least one group
of proposed theistic explanations—those which posit miracles—seems
doomed to failure.
But was Hume right? Hume’s apparently simple argument, which he
hoped would settle the question once and for all, 55 is still being debated.
I cannot hope to end the debate here. Let me just point out a weakness in
Hume’s argument, which highlights the need for a fuller discussion. The
argument rests on the idea that we can estimate the prior probability of a
miracle occurring, and that this prior probability is exceedingly low. But