In his massive work Summa Theologica, Thomas Aquinas wrote five logical proofs for the existence of God, popularly called The Five Ways. The first way involves causality and motion, and is often misunderstood. Most, if not all, of modern strident atheists miss the concept entirely. Dr. Richard Howe has rightfully explained the point in an article that he published on his website. Thomas’ first way goes like this:
It is therefore impossible that in the same respect and in the same way a thing should be both mover and moved, i.e. that it should move itself. Therefore, whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.
Many critics have a field day taking pot shots at this. If dominoes are falling over, what does yesterday’s domono have to do with today’s domino? Why can’t one thing cause another, which caused another, on to infinity? Thomas is accused of making an obvious logical leap. Critics say that if a grandfather causes a son, then the grandfather need not be around to cause the grandson. This motion could go on to infinity, so the critics’ claim. Thomas is accused of assuming a first mover, then trying to prove a first mover, a classic circular argument.
But as Howe points out, this criticism totally misses Thomas’ argument. Notice the analogy at the end: “…as the staff moves only because it is put in motion by the hand.” It could be that a hand is moving a staff, which is in turn moving a stone, which is in turn flattening a bug. This is a chain of objects moving only because there is a hand moving it. The only reason the bug gets squashed is because there is a stationary human that is moving the stone with a stick. All the objects are moving at the same instant. The bug won’t get squashed unless the hand is a current, ongoing cause of movement. This cause of movement cannot go on to infinity…..there must be a first mover. If there were not a stationary, first mover, then the whole sequence could not move. Thomas is not speaking of sequential movement, as in a grandfather causing a son, or one domino pushing another domino. Rather, the movement is all current movement. If the last link of a chain is moving, the first one must be moving also, and a moving chain cannot move itself. The staff cannot push the stone unless somewhere toward the begining, there is a source of movement that is stationary. And the source of movement must be fundamentally different than the series of objects being moved. If a series of chain links are moving, then whatever is moving them cannot be a chain link, but must be something else, and this something must be stationary.
This concept is totally lost on the critics of Thomas Aquinas’ Five Ways, and lost on the critics of the Christian apologetics that have resulted from Thomas, such as the cosmological argument. In effect, a 750-year-old philosopher has blown a fastball right by them, and they never really saw the ball.