A couple of comments on Reppert “The Argument from Reason” in Craig and Moreland (ed.) Blackwell Companion to Natural Theology, 344-90. (I have a long list; I may post further comments later.)
1. At 368, Reppert argues: If the reference of our terms is indeterminate, then this has the disastrous consequence that we cannot reason to conclusions.
This is surely wrong. Reasoning can be purely formal. (If all flombs are bloops, and all bloops are shimbs, then all flombs are shimbs. The reasoning is impeccable. We can reason even if our terms have no meanings!) Moreover — and perhaps partly in consequence — so long as we restrict ourselves to a single context, and use the same word throughout, we can reason perfectly well even if our meanings are indeterminate. (If this is a rabbit, and that is a distinct rabbit, then there are at least two rabbits. Fine, regardless of Quinean indeterminacy in the meaning of “rabbit”!)
2. At 374, Reppert endorses an argument by Menuge, for the conclusion that our intentionality is the product of prior intentionality. This argument begins as follows:
1. If something has a purpose, then it is designed.
2. Intentionality has the purpose of guiding behaviour.
3. (So) Intentionality is designed.
This argument cannot be good … and, in particular, Reppert cannot think that it is good. After all, he does NOT think that God’s intentionality is designed.