The Argument from Desire: Longings That Point Beyond

C.S. Lewis once observed something remarkable:

for every natural desire we have, there exists a real fulfillment.

• Babies are hungry—food exists. 
• Ducklings want to swim—water exists.
• Men have sexual desires—sex exists.

These desires are not accidents, they are built into us, and they point to something outside ourselves that can satisfy them.

But there is another desire, deeper and more elusive: the longing for transcendence, eternity, and ultimate meaning. No matter how much we eat, drink, achieve, or even love, nothing in this world seems to fully quench it. As Lewis put it, if we find ourselves with a desire nothing in this world can satisfy, the most reasonable explanation is that we were made for another world.

Some might object: “But we can imagine desires for things that don’t exist—like pet dragons or gadgets that haven’t been invented yet. Doesn’t that prove desire doesn’t always point to reality?” The answer is that not all desires are the same. Lewis distinguished between natural desires (which are universal, cross-cultural, and rooted in human nature) and artificial desires (which are products of imagination or culture). A dragon is an artificial desire—just a flight of fancy. A push-to-start button is an artificial desire too—born from human creativity, and in that case fulfilled by technology. But natural desires like hunger, thirst, companionship, or transcendence are of a different order. They are woven into our very being, and unlike fantasies, they always correspond to something real.

Naturalism can try to explain how such desires or fears evolved, but it struggles to explain why we all share this unshakable longing for something infinite, something no finite good can supply. Hunger helps us survive, fear keeps us safe, but what evolutionary advantage is there in yearning for the eternal?

That's why Lewis said desire is teleological—oriented toward fulfillment. To dismiss this longing as mere fantasy is to make the universe into a cruel joke, teasing us with a thirst it cannot quench. But to take it seriously is to recognize it as a signpost. The dragon-desire shows imagination, while the God-desire points to transcendence.

C.S. Lewis, 1898 - 1963