Peter Kreeft explains how our innate, unmet desire for something beyond the "finite and partial" argues for the existence of God:
- Every natural, innate desire in us corresponds to some real object that can satisfy that desire.
- But there exists in us a desire which nothing in time, nothing on earth, no creature can satisfy.
- Therefore there must exist something more than time, earth and creatures, which can satisfy this desire.
- This something is what people call "God" and "life with God forever."
The first premise implies a distinction of desires into two kinds: innate and externally conditioned, or natural and artificial. We naturally desire things like food, drink, sex, sleep, knowledge, friendship and beauty; and we naturally shun things like starvation, loneliness, ignorance and ugliness. We also desire (but not innately or naturally) things like sports cars, political office, flying through the air like Superman, the land of Oz and a Red Sox world championship.
Now there are differences between these two kinds of desires. We do not, for example, for the most part, recognize corresponding states of deprivation for the second, the artificial, desires, as we do for the first. There is no word like "Ozlessness" parallel to "sleeplessness." But more importantly, the natural desires come from within, from our nature, while the artificial ones come from without, from society, advertising or fiction. This second difference is the reason for a third difference: the natural desires are found in all of us, but the artificial ones vary from person to person.
The existence of the artificial desires does not necessarily mean that the desired objects exist. Some do; some don't. Sports cars do; Oz does not. But the existence of natural desires does, in every discoverable case, mean that the objects desired exist. No one has ever found one case of an innate desire for a nonexistent object.
Kreeft argues for the second premise and conclusion and then responds to objections here.