Observation:
Among living things, we can distinguish "creator" and "created."

Speculation:
We can speculate that non-living phenomena are also created.

Observation:
Nothing, living or inert, that we see around us demonstrates that it created or could have created itself.

Speculation:
All that we perceive must have been created by something.

Observation:
That which is living demonstrates its ability to pro-create its own kind, but nothing living demonstrates the ability to pro-create outside its own category of being.

Speculation:
That which is non-living, likewise, cannot create outside of its own category of being.

Observation:
We can perceive the "cause/effect" relationship between generations of being, projecting future generations and accounting for generations in our relative past.

Speculation:
As we reflect backwards, we are lead, by necessity,  to the concept of the "first cause" and to question its nature.

Argument:
1) If all in the physical universe has been created, and

2) If nothing in the physical universe has created itself, and

2) If nothing in the physical universe can create new categories of being, therefore

3) the creator of the physical universe must be non-physical.

This argument enters Western Christian religious thought and theology through the writings of St. Thomas Aquinas in the Roman Catholic Church.  He addressed the problem in his treatise (essay), "On Causes."

Online Connection
To read more on the concept of God as "first cause," see "The Doctrine of Causality in Aquinas and The Book of Causes:
One Key to Understanding the Nature of Divine Action."

Our Course Connection
In his "Age of  Reason," Thomas Paine repeats the argument above in his attempts to justify Deism as the only natural religion.
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