In his Pensees Pascal describes his despair at what can be known about God through nature alone:
This is what I see and what troubles me. I look around in every direction and all I see is darkness. Nature has nothing to offer me that does not give rise to doubt and anxiety. If I saw no sign there of a Divinity I should decide on a negative solution: if I saw signs of a Creator everywhere I should peacefully settle down in the faith. But seeing too much to deny and not enough to affirm, I am in a pitiful state…
We are truly in a pitiful state if all we can know of the meaning of ‘life’ is what we discover through our senses. We look up at the great, majestic trees of the forest and feel that they must be the work of God but then recoil in horror when we watch the grim drama that unfolds on their branches when a parasite takes control of the mind of an ant and causes it, in the last moments of its life, to lock onto a leaf stem with its mandibles and become an incubator for the next generation of deadly fungus.
It would be better that God had not revealed himself to us at all than leave us alone with the light of nature… As Pascal put it,
“I have wished a hundred times over that, if there is a God supporting nature, she should unequivocally proclaim him, and that, if the signs in nature are deceptive, they should be completely erased; that nature should say all or nothing so that I could see what course I ought to follow. Instead of that, in the state in which I am, not knowing what I am nor what I ought to do, I know neither my condition nor my duty. My whole heart strains to know what the true good is in order to pursue it: no price would be too high to pay for eternity.”
So nature makes us thirsty but it doesn’t satisfy our thirst.