The strategy that we adopt for breaking this tie in modal intuitions is to show that one of
the two rival modal intuitions coheres better with other of our background modal
intuitions. To begin with, our belief in W-PSR coheres better with our proclivity to seek
an explanation for any contingently true proposition. That we seek such an explanation
shows that we do accept W-PSR, for we would not seek an explanation if we did not
believe that it is at least logically possible that there is one. Second, we know what it is
like to verify that a given proposition has an explanation, namely, by discovering an
explanation for it, but we do not know what it is like to verify that a given contingently
and verifiably true proposition does not have an explanation. Furthermore, since we know
what it is like to verify that a proposition has an explanation, we know what it is like to
verify that it possibly has an explanation, given that actuality entails possibility. We do
not, however, know what it is like to verify that a proposition does not possibly have an
explanation: there are just too many possible worlds for that to be accomplished. It is
beside the point to respond that we know how to falsify the proposition that some
proposition does not have an explanation but not the proposition that it has an
explanation, since a proposition's truth-conditions are directly tied to its conditions of
verification, not those for its falsification. These two considerations lend credence to the
claim that, in the epistemic order, W-PSR is more deeply entrenched than is the Davey-
Clifton claim that it is possible that a given contingent proposition has no explanation.
From this conclusion it is reasonable to infer that, in the logical or conceptual order, W-
PSR is a better candidate than is the Davey-Clifton proposition for being possible.
Teleological Arguments
The teleological argument for the existence of God, or at least for a designer of the
universe, has never received a more rhetorically powerful formulation than in William
Paley's (1802) analogy of the watch. We find a watch lying on a heath. We examine it.
We see that its parts fit and work together in an intricate manner, and infer that the watch
was designed by an intelligent agent. The inference could
end p.127
be made even if we had never seen a watch before. Similarly, when we look at biological
mechanisms, we descry a similar complexity and we should likewise infer that the
biological mechanisms were designed, but by a proportionately more intelligent being.
The argument does not tell us much about the designer, but we can at least infer that the
ultimate designer is at least in part immaterial. For if the designer were a physical being,
he too would have intricately put together parts, since any completely material intelligent
being will have to be constituted out of a number of carefully interrelated parts, and the
argument from design could be repeated. But a regress could be argued to be vicious here
for reasons similar to those in the cosmological argument: if there was just an infinite
regress, the complexity of design would never get explained. Moreover, we have
empirical reasons against accepting an infinite regress of physical beings as designers,
namely, the empirical evidence that our universe has finite age.