Sometime after the Enlightenment, science and religion came to a gentleman's agreement. Science was for the real world: machines, manufactured things, medicines, guns, moon rockets. Religion was for everything else, the immeasurable: morals, sacraments, poetry, insanity, death, and some residual forms of politics and statesmanship. Religion became, in both senses of the word, immaterial. Science and religion were apples and or anges. So the pact said: render unto apples the things that are Caesar's, and unto oranges the things that are God's. Just as the Maya kept two calendars, one profane and one priestly, so Western science and religion fell into two different conceptions of the universe, two different vocabularies.