schiz­o­phre­nia did not rise in preva­lence until the lat­ter half of the 18th cen­tu­ry, when for the first time peo­ple in Paris and Lon­don start­ed keep­ing cats as pets. The so-called cat craze began among “poets and left-wing avant-garde Green­wich Vil­lage types,” says Tor­rey, but the trend spread rapidly—and coin­cid­ing with that devel­op­ment, the inci­dence of schiz­o­phre­nia soared