Previously in this thread, I presented demonstrations of the existence of God. Respondents to the demonstrations adamantly maintained several false assumptions about the meaning of the arguments, and thus their criticisms amounted to nothing more than straw man fallacies.
In his *
Summa Theologica, *Thomas Aquinas presents five philosophical demonstrations of the existence of God. While the arguments do not, and are not intended as proofs for the existence of the personal God of the Judeo-Christian, they are more limited in that they demonstrate the existence of a supreme being who
transcends the universe. And this is what we mean by “God”.
In addition, the legitimacy of arguments’ proofs are not contingent on whether the universe is conceived as finite or infinite. In fact, it must be kept in mind that the arguments make the philosophical presumption that the universe has always existed. That is, the demonstrations do not argue against the idea that the universe has not always existed. Hence, any attempted criticism of the arguments based on the assumption that the universe has always existed, or that matter and energy have always existed, will have most likely misunderstood Aquinas’ demonstrations from the outset. Hopefully, any new critics of the arguments will not commit that commonplace error.
Aquinas says,
"The existence of God can be proved in five ways.
“The first and more manifest way is the argument from motion. It is certain, and evident to our senses, that in the world some things are in motion. Now whatever is in motion is put in motion by another, for nothing can be in motion except it is in potentiality to that towards which it is in motion; whereas a thing moves inasmuch as it is in act. For motion is nothing else than the reduction of something from potentiality to actuality. But nothing can be reduced from potentiality to actuality, except by something in a state of actuality. Thus that which is actually hot, as fire, makes wood, which is potentially hot, to be actually hot, and thereby moves and changes it. Now it is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects. For what is actually hot cannot simultaneously be potentially hot; but it is simultaneously potentially cold. 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.”
I will use the following restatement of the foregoing argument from motion as follows:
- Our senses prove that some things are in motion.
- Things move when potential motion becomes actual motion.
- Only an actual motion can convert a potential motion into an actual motion.
- Nothing can be at once in both actuality and potentiality in the same respect (i.e., if both actual and potential, it is actual in one respect and potential in another).
- Therefore nothing can move itself.
- Therefore each thing in motion is moved by something else.
- The sequence of motion cannot extend ad infinitum.
- Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.
But let me say up front that it’s pretty cheeky for man to claim that the natural world is unable to account for its own existence. We’re just taking our first baby steps in understanding the world in which we live. We have a long way to go before concluding that something is beyond the capability of nature and resorting to a supernautural explanation.
