One time Fat found a posted notice that fascinated him. The notice stipulated what could not be done, in order of descending importance. Near the top of the list all parties concerned were told: NO ONE IS TO REMOVE ASHTRAYS FROM THE WARD. And later down the list it stated: FRONTAL LOBOTOMIES ARE NOT TO BE PERFORMED WITHOUT THE WRITTEN CONSENT OF THE PATIENT. ‘That should read “prefrontal”,’ Doug said, and wrote in the ‘pre’. ‘How do you know that?’ Fat said. ‘There’s two ways of knowing,’ Doug said. ‘Either knowledge arises through the sense organs and is called empirical knowledge, or it arises within your head and it’s called a priori.’ Doug wrote on the notice: IF I BRING BACK THE ASHTRAYS, CAN I HAVE MY PREFRONTAL? ‘You’ll be here ninety days,’ Fat said.
Philip K Dick, Valis