David Vander Laan

The theory of possible worlds has permeated analytic philosophy in recent decades, and its best versions have a consequence which has gone largely unnoticed: in addition to the panoply of possible worlds, there are a great many impossible worlds. A uniform ontological method alone should bring the friends of possible worlds to adopt impossible worlds, I argue, but the theory's applications also provide strong incentives. In particular, the theory facilitates an account of counterfactuals which avoids several of the implausible results of David Lewis's account, and it paves the way for the analogues of Kripkean semantics for epistemic and relevant logics. On the theories of possible worlds as abstract objects, worlds bear a strong resemblance to propositions. I contend that if there are distinct necessarily false propositions, then there are likewise distinct impossible worlds. However, one who regards possible worlds as concrete objects must not recognize impossible worlds, in part because concrete worlds cannot misrepresent certain features of reality, as some impossible worlds must. Accordingly, I defend and develop a theory of impossible worlds as maximal impossible states of affairs. Impossible worlds perform admirably in the analysis of counterfactuals with impossible antecedents. I argue that, contrary to standard accounts, not all counterpossibles are trivially true, and I develop a Lewis-style semantics which allows this result. The point is crucial, since many views presuppose that some counterpossibles are substantive philosophical truths. Finally, I show that impossible worlds hold great promise for doxastic and relevant logics. Epistemic logic needs a domain of propositions which is not closed under strict implication to avoid the problem of logical omniscience, and relevant logic needs such a domain to avoid the famous paradoxes of implication. In sum, impossible world theory promises natural, elegant solutions to philosophical problems in numerous areas where possible worlds alone flounder. These solutions come to most possible world theorists at no cost, since the existence of impossible worlds is entailed by theses they already hold.

In much of Christian thought humans are taken to have an ultimate end, understood as the highest attainable good. Christians also anticipate “the life everlasting.” Together these ideas generate a paradox. If the end can be reached in a finite amount of time, some longer-lasting state will be better still, so the purported end is not the highest good after all. But if the end is to possess some good forever, then it will never be reached. So it seems an everlasting being cannot have an ultimate end—a conclusion that apparently makes human life pointless. How can the paradox be solved?

This chapter focuses on one of the common fallacies in Western philosophy called “adverse consequences”. The argument from adverse consequences can be seen as an argument that is intended to be pragmatic ‐ about what we should do, not about what is true ‐ but then comes to the wrong kind of conclusion. In many genuinely pragmatic arguments, however, adverse consequences are relevant to the conclusion and no fallacy is committed. So it is important to notice exactly what the conclusion of the argument is.

Arguments concerning divine conservation and concurrence often assume that actions of certain descriptions would be superfluous if God were to perform them, and it is then concluded that God does not perform such actions. In particular, it often seems that atomic actions cannot be the result of cooperative activity between God and creatures since there is no apparent way to divide the labor between the two. However, the actions that are atomic in one model of divine action may not be atomic on another. On fine-grained models there may be unexpected prospects for nonredundant divine action.

Against the historically widespread view that divine conservation is a continuation of the act of creation, William Lane Craig argues that conservation is a different kind of act since, unlike creation ex nihilo, it is diachronic and it acts on a patient. Timothy Miller poses a timing objection against Craig's view, arguing that on such a view either the existence of a conserved entity is discontinuous, or the conserving activity overdetermines its effect, or the conserving activity is not continuous. The present paper explores the options that remain for a diachronic, agent-patient account of conservation. It includes several models of conservation on which divine activity is continuous but not overdetermined since its effect at each time is something less specific than the existence of a created being at a time.