The Talmud teaches us (Berachot, 21a) that the requirement to say a blessing after a meal comes from a verse in the Torah (Deuteronomy 8:10), and to recite it before the meal comes from a logical imperative. But the reverse is true with Torah study; the source for reciting a blessing before is from a verse (Deut. 32:3).
The Vilna Gaon points to this difference — a specific verse mandating before a meal and another verse for one after Torah study — and explains it. We are instructed to bless after the meal because although before we are hungry and eager, after we no longer feel hunger and are less likely to take the trouble. But although physical yearning peaks before indulging, spiritual hunger is the reverse. Only after we study Torah are we fully aware of the depth and beauty of learning.
So it is with physical and spiritual pleasures in general. The human appetite for physical pleasures is greater before, and for spiritual pleasures greater after. Although the Vilna Gaon is rarely paired with Ernest Hemingway, here they fit together nicely: For both physical and spiritual pleasures, as Hemingway said, “Good is what feels good after.”