Beckett's novel Watt portrays the titular protagonist in the midst of a world which has crumbled. Watt attempts to solace and comfort himself by constructing logically complete and correct mental systems. These systems are the famous lists, series, combinations, and permutations which constitute a third of the novel. Little attention has been paid to this major feature of Watt. A close examination, however, uncovers enough unobtrusive but real flaws (omissions, incorrect items) in these series and combinations to support the conclusion that these mistakes are deliberate. Thus, Watt's attempts at an internal personal system, and the personal systems themselves, are as unreliable as the external world.