1. PHIL/RS 335 Arguments for God’s Existence Pt. 1: The Cosmological Argument

2. Going back to the beginning.  The cosmological argument has its origin in Ancient Greek Philosophy.  We see versions of the argument in the work of both Plato and Aristotle.  There, of course, the argument was not aimed at proving the existence of a theistic divinity, but at explaining the origin of the world.

3. The CA in the History of Philosophy  In the forms more familiar to us, the aim of the argument is proving the existence of the God of the traditional monotheisms.  Historically, there are two periods of particularly intense interest in the cosmological argument.  The first is in the 13 th century, due to the influence of Thomas Aquinas, whose first 3 proofs for the existence of God in the section of the text entitled “The Five Ways,” are various versions of the cosmological proof.  The second is in the 18 th century, when the work of two prominent advocates of the argument, Leibniz and Samuel Clarke was at the zenith of its influence.  Though there continue to be advocates of versions of the CA, most contemporary philosophical theists have voiced skepticism about the argument.

4. What is it?  As should already be apparent, the cosmological argument is really a family of arguments which share a basic structure.  Though there are significant variations which we will have to account for, the various versions of the CA begin with certain relatively non- controversial descriptions of the natural world and infer from them the existence of a necessary being, which they then argue must be understood as God.

5. Aquinas’s Five Ways  As already noted, only the first three arguments offered by Aquinas are versions of the cosmological argument. 1.Argument from Motion 2.Argument from Efficient Causality 3.Argument from the Existence of Contingent Beings  An examination of these three arguments reveals a common set of elements.  They are all a posteriori arguments, starting with observation and reasoning to conditions.  They all assume the impossibility of infinite regress.  Strictly speaking, they don’t quite get us to God, but rather, to what, “…everyone understands to be God.”

6. Evaluation of these elements.  The class of arguments we are calling a posteriori arguments are common and generally non-controversial, though they are most frequently developed as inductive, rather than deductive arguments.  The claim of the impossibility of infinite regress is much more controversial. Copleston, in the inset on p. 62, tries to rescue this claim by insisting that Aquinas’s assertion is an ontological rather than temporal or genetic claim, but set-theoretic mathematics provides the resources for serious reservations here.  The point of the last observation is to highlight that even if we grant the force of the arguments offered by Aquinas, we don’t seem to get the God of theism. We might get a first mover, a first efficient cause, or a necessary being, but not the loving, personal God which traditional theism is committed to.

7. A More Modern Version  Both Leibniz and Clarke combined an attempt to use the principle of sufficient reason to establish the existence of a self-existent being and then argue that such a being is best understood as the God of theism.  The first step in the argument can be summarized as follows. 1.Every being is either a dependent being or a self-existent being. 2.Not every being can be a dependent being. __________________________ Conclusion: There exists a self-existent being.  Definitions  Dependent Being: a being whose existence is accounted for by the causal activity of other things.  Self-Existent Being: a being whose existence is accounted for by its own nature (what the Yandell’s refer to as “existential security”).

8. Explanation of Premise 1  For Leibniz and Clarke (and the Yandells) the truth of the first premise is established by the Principle of Sufficient Reason.  The PSR is commonly formulated as “Everything has a reason,” though it can be formulated in a number of more specific ways (see 69c2). What does this mean? There are a number of possibilities.  There must be an explanation a)for the existence of any being; b)of any positive fact whatsoever (73c2); c)of the cosmic whole.

9. Explanation of Premise 2  There are two ways commonly employed to establish the second premise.  The first is Aquinas’s: there can be no infinite series.  The second is the assertion that there are no brute facts. That is, there has to be an explanation of why there is anything at all (82c1).  Consider the following causal chain A 1 —A 2 —A 3 —A n —A n+1  Relative to any A, the PSR is satisfied, but what about the chain as a whole?  Only the assertion of the second premise would seem to satisfy the PSR for the chain.

10. Criticisms of the 2 nd Premise  Makes a category mistake. Assumes that the series is of the same ontological order of the elements of the series.  Commits the Part/Whole Fallacy. All humans have mouths, but that doesn’t mean that the category “human being” has a mouth.  Hume, Dialogues Concerning Natural Religion, Pt. IX, “Did I show you the particular cause of each individual in a collection of twenty particles of matter, I should think it very unreasonable, should you afterwards ask me, what was the cause of the whole twenty. This is sufficiently explained in explaining the cause of the parts.”

11. Criticisms of Premise 1  Why should we accept the PSR?  Is it intuitively true? Does reason presuppose it? If an explanation seems possible, does that mean there is one (Yandells 76c1)?  Mackie identifies a number of arguments which call these justifications into question (79c2-81c2). 1.Contra Clarke, the PSR doesn’t seem to fit with what we know of human behavior. 2.What about the requirements of reason? Scientific inquiry (philosophical or otherwise) requires causal inquiry of the intra-series sort, but all such inquiry begins in posits, and these don’t seem to require the PSR. 3.What about purposiveness? We often desire that there be an absolute purpose, but surely thinking of our lives as purposeful doesn’t require an absolute purpose.  “We have no right to assume that the universe will comply with our intellectual preferences” (81c2).  See also the Rowe inset on p. 80.