The paraphrase of Gรถdel's Theorem says that for any record player, there are records which it cannot play because they will cause its indirect self-destruction.
Douglas HofstadterYou can never represent yourself totally .... to seek self -knowledge is to embark on a journey which ... will always be incomplete, cannot be charted on a map, will never halt, cannot be described.
Douglas HofstadterFor 13 to be unlucky would require there to be some kind of cosmic intelligence that counts things that humans count and that also makes certain things happen on certain dates or in certain places according to whether the number 13 'is involved' or not (whatever 'is involved' might mean).
Douglas Hofstadter