Ed. James Sennett. Eerdmans.
Unlike some anthologies, this isn’t simply a Plantinga chapter here and a long snippet there. True, there are some reproduced chapters (see his legendary “Reason and Belief in God”) but other chapters in the book, while not necessarily giving new material, present it in a new format. A few chapters take key passages from his notoriously difficult Nature of Necessity and present it without the modal logic, making for an easier read.
The first section of the book explores his early and later approaches to natural theology, the ontological argument, and free will. A word on the latter: more Reformed readers do not have to accept some of his conclusions in order to appreciate his analysis of Possible Worlds Semantics. Per the ontological argument,
(22) It is possible that there is a greatest possible being.
(23) Therefore, there is a possible being that in some world W’ or other has a maximum degree of greatness.
(24) A being B has the maximum degree of greatness in a given possible world W only if B exists in every possible world.
(25) It is possible that there be a being that has maximal greatness.
(26) So there is a possible being in some world W that has maximal greatness.
This is an early form of his argument, especially since the modal operators are lacking. But we can add the conclusion:
(27) It is possible that a necessary being exists.
(28) A necessary being exists.
Does the argument work? It depends on whether you think S5 modal logic is true or not. If it is true, the argument holds.
Reason and Belief in God
The issue: must I satisfy some norm to hold Belief B? If knowledge = justified, true belief, then what duty must I fulfil in order to have a rational belief? The modern answer to this question is seen in some form of foundationalism: what is a properly basic belief?:
(1) Self-evident or evident to the senses
(2) Incorrigible (for example, if I see a tree, I could be mistaken, but I am not mistaken that I think I see a tree)
(3) Which denial leads to a contradiction.
We will call (1)-(3) the Foundationalism Thesis (FT).
The problem with the above is that very few beliefs meet those criteria. In fact, the thesis itself doesn’t meet the criteria. FT isn’t self-evident, it’s not incorrigible, and rejecting it doesn’t violate any laws of logic. Even more striking, this seems to mean that the theist is warranted in believing in God even if he hasn’t bothered to meet the FT.
The last section is a collection of encouraging chapters on how to do Christian philosophy in a secular guild.