I was searching for another, unrelated quote, but I came across this one, and a particular statement intrigued me.
The books or the music in which we thought the beauty was located will betray us if we trust to them; it was not IN them, it only came THROUGH them, and what came through them was longing. These things--the beauty, the memory of our own past--are good images of what we really desire; but if they are mistaken for the thing itself, they turn into dumb idols, breaking the hearts of their worshippers. For they are not the thing itself; they are the scent of a flower we have not found, the echo of a tune we have not heard, news from a country we have never visited. Do you think I am trying to weave a spell? Perhaps I am; but remember your fairy tales. Spells are used for breaking enchantments as well as for inducing them. And you and I have need of the strongest spell that can be found to wake us from the evil enchantment of worldliness which has been laid upon us for nearly a hundred years. Almost our whole education has been directed to silencing this shy, persistent, inner voice; almost all our modern philosophies have been devised to convince us that the good of man is to be found on this earth. - C.S. Lewis, The Weight of Glory
The bolded portion is what intrigued me. What began a hundred years before C.S. Lewis wrote this? What might he be referring to?