Friday, November 17, 2006

Modal Realism and the Cosmological Argument

It seems to follow from a certain kind of realism about metaphysical possibilities that a version of the cosmological argument goes through. The idea is that if the space of possibilities exists, then it exists necessarily. The actualized concrete events of the world are contingent and depend on the necessary space of possibilities.

There are many variations, but the cosmological argument states that the chain of events needs a necessary first cause to get started. Or else it is cast in terms of arguing that contingent things ultimately must depend on a necessary self-existent thing. In the model under consideration here contingent things (events) are actualizations of possibilities. A given event is subject to causal constraint by prior or adjacent events but is always also dependent on the space of possibilities.

There seems to be no well motivated reason to consider an objection involving, say, an infinite chain of meta-modal spaces upon which the first-order space of possibilities depends. So, the space of possibilities would be a self-existent necessary entity and the argument goes through.

[UPDATE: 5 February 2009 -- This modal realism-inspired cosmological argument should not be confused with other arguments which goes by the name "modal". These arguments (which doesn't work IMO) try to use modal logic to imply theism: see discussion here for instance.]

1 comment:

Steve said...

It was brought to my attention that this post was poorly written and filled with jargon. So here is another take:

If you believe that each event in the world really could have happened differently, then you believe possibilities are real. If one pictures reality as including not just actual events but all of the possible events (modal realism to the philosophers), then this is one way to get to the idea of our world being just a subset of a larger reality. And it makes sense to me that this larger reality, taken as a whole, must exist of necessity (the whole sum of possibilities can't just be one more possibility). And this conclusion is somewhat analogous to the conclusion of a version of the cosmological argument for the existence of God espoused by Leibniz and others.