The most difficult yet most important book (outside of Bible) I have read. Somebody described this book perfectly: “I felt like I was up against a Level 97 Boss and I was only Level 70.”
Plantinga begins his survey of modal ontology with a discussion of de re and de dicto statements.
de dicto: predicates a modal property of another dictum or proposition (Plantinga 9).
de re: x has a certain property essentially.
The problem: “suppose we are given the object x and a property P. Is it possible to state general directions for picking out some proposition–call it the kernel proposition with respect to x and P–whose de dicto modal properties determine whether x has P essentially” (30)?
While such a question seems arcane, it does allow Plantinga to furnish the theist with a number of highly useful concepts and tools, like possible worlds. A possible world is the way things could have been, a possible state of affairs (44). But not every possible world is a possible state of affairs. “A state of affairs must be maximal or complete.”
From this Plantinga gives a fine, if not always lucid, presentation of essence and nature. An essence could also be a set of properties (76). An essence is a set of world-indexed properties (i.e., that is those which exist in every possible world; 77). Essential properties: the properties Socrates has in every world he exists. Essence: the instantiation of the above properties.
Plantinga uses these tools to deal with the atheologian’s problem of evil. First of all, what is freedom? Freedom: no causal laws and antecedent conditions determine whether I will or will not act.
The initial defense: a world containing creatures who are sometimes significantly free is more valuable, all things considered, than a world with no freedom (166). Therefore, creatures that are capable of moral good are also capable of moral evil.
The problem: if God is omnipotent, then how come he couldn’t create a world where all the creatures freely do what is good? Plantinga takes a brief detour and clarifies what we mean by creation. God does not create everything (e.g., he does not create his own properties, for example). Rather, God creates some things and God actualizes states of affairs (169).
Plantinga gives a rather dizzying survey of the Ontological Argument. While I have my doubts on its psychological efficacy in debates, the Ontological Argument, especially Plantinga’s retelling of it, serves a crucial role in defining what we mean by God and what it means for God to have properties.
This allows Plantinga to utilize the concept of Transworld Depravity: Every world that God actualizes, given person P’s freedom, P takes at least one wrong action (185). It is possibly true (not necessarily) that any world God actualizes has P doing wrongly.
Plantinga concludes his discussion with the Ontological Argument. The crux of the matter is this: a) is existence a predicate? b) is existence a great-making property?
Kant denies (a). I am not sufficient to judge whether he is right or not. In any case, (b) is more interesting. Can (b) be proven adequately to the unbeliever? Maybe, maybe not. However, for the believer for whom the existence of God is already a settled issue (whether rightly or wrongly) (b) certainly follows (and thus informs one’s systematic theology).
Further, given Plantinga’s possible worlds semantics, a maximally great being will exist in every possible world.
This is the hardest book I’ve ever read. The above is a fourth grade summary of what I think Plantinga said. The appendix on symbolic logic is like what math would look like if it were designed by Satan.
I found a lot of useful logical tools. I am not sure all of Plantinga’s arguments are fully developed. For example, I like the idea of transworld depravity. I am just not sure why the atheologian will not object in the following way: “Why could God not create a world in which transworld depravity doesn’t obtain? Must freedom then entail transworld depravity?” Indeed, this is problematic for the doctrine of creation.