“He was possessed of a belief that nothing existed, or to be more precise, that only when things were perceived could we be sure that they existed. He troubled himself in arguments, therefore, that when he was not in his chamber, and no one else was in his chamber, there was no one who could say beyond a shadow of a doubt that his desk still existed... or that the bed had not simply frayed into atoms...[Dr. 03-01] developed the habit of quietly leaving company quite suddenly and charging above-stairs to his bedchamber, throwing open the door, and crying "Ah ha!" He found, always, that matter had retained its dubious solidity in his absence; but this did not deter him.”