Monday, January 9, 2012

Aquinas and the five ways (well one of them)

In anticipation of a possible discussion on a Facebook atheist group (to which I was invited, unimpressed, and subsequently in the process of being re-invited) I offer the following presentation of Aquinas five ways to prove the existence of God.  This blog post will discuss the first way.

As having established that science (more specifically scientism) is insufficient to discern truths about the scientific method and thus cannot provide all truths that can be discerned, we now turn to Aquinas and the first of the five ways of demonstration for the existence of God. (this is excerpted from here):

St. Aquinas argues that there are things in the world in motion (this simply means that things are changing) and that whatever is in motion must have been put in motion by another thing in motion. Aquinas holds that, "whatever is in motion must be put in motion by another," and that, "this cannot go on to infinity, because then there would be no first mover." Hence St. Thomas argues that in order to eliminate the infinite chain of motions, there must be a first mover and source of all motion, God.
It is important to understand that "motion"  in this case means "change."  Any entity that exists in the physical world is in change, and that change is created by an external cause.  This is true for the universe as well (justified inference) as each and every component shares this property.  So we have the case where some change in an entity is caused by another entity, and so on.  This chain of causality however cannot go on for infinity, otherwise we would not have arrived at whatever current cause we start with when walking back.  Thus there must be a starting point, a cause that was not caused by another.  This we call God.

First the bad arguments that object to this:

Who created God?  - this is nonsensical with regard to the definition of God in this case as the question means: "Who caused the un-caused cause?"  The question cannot be answered because it is a self contradiction.

Uniform motion and rest are the same - This is a misunderstanding of the term "motion" as used by Aquinas.  What he means by "motion" we mean by "change."

Rehash of the ontological argument - this error is caused by misunderstanding the concept of "necessary being."  In the cosmological argument, necessary being only pertains to the necessity of God's existence to stop the infinite chain of causation.

Finally a good argument:

Composition fallacy - This is countered by noting that the universe is a composition of contingent parts.  By virtue of the contingency of the parts, the universe is contingent.  This follows from the notion that an individual part that, if it did not exist, would change the composition of the universe.

No comments: