Newsgroup: it.hobby.enigmi
Titolo: un problema di Carroll

Salve,
leggendo un vecchio libro di gardner vi ho trovato un riferimento ad
un priblema di logica ricreativa inventato da lewiss carroll e del
quale, pur lodandone la costruzione, non ne riportava il testo.
Diceva solo che era di 13 sentenze e riguardava magistrati fumatori di
tabacco.
Qualcuno ne possiede il testo completo?
grazie
sergio

"Evaluation Version" richiede:

Ciao, anche io a suo tempo ho cercato tale problema ma non mi sembra
esistere; nell'appendice di Symbolic Logic vi sono, si, vari problemi
"mostruosi" ma non ne vedo uno che riguarda magistrati e tabacco. Come
esempio te ne riporto uno qui sotto ma ve ne sono anche molti altri. Se ti
interessa ho il testo intero del libro in formato .txt, puoi scrivermi
all'indirizzo gascar(chiocciola)iolpuntoit per averne una copia. Fammi
sapere,
GaS
=======================================
 All the boys, in a certain School, sit together in one large
room every evening.  They are of no less than five nationalities
---English, Scotch, Welch, Irish, and German.  One of the
Monitors (who is a great reader of Wilkie Collins' novels) is
very observant, and takes MS. notes of almost everything
that happens, with the view of being a good sensational
witness, in case any conspiracy to commit a murder should
be on foot.  The following are some of his notes:---
       (1) Whenever some of the English boys are singing
         "Rule Britannia", and some not, some of the
         Monitors are wide-awake;
       (2) Whenever some of the Scotch are dancing reels,
         and some of the Irish fighting, some of the Welsh
         are eating toasted cheese;
       (3) Whenever all the Germans are playing chess, some
         of the Eleven are not oiling their bats;
       (4) Whenever some of the Monitors are asleep, and
         some not, some of the Irish are fighting;
       (5) Whenever some of the Germans are playing chess,
         and none of the Scotch are dancing reels, some of
         the Welsh are not eating toasted chees;
       (6) Whenever some of the Scotch are not dancing reels,
         and some of the Irish not fighting, some of the
         Gemans are playing chess;
       (7) Whenever some of the Monitors are awake, and
         some of the Welsh are eating toasted cheese, none of
         the Scotch are dancing reels;
       (8) Whenever some of the Germans are not playing
         chess, and some of the Welsh are not eating toasted
         cheese, none of the Irish are fighting;
       (9) Whenever all the English are singing "Rule
         Britannia," and some of the Scotch are not dancing
         reels, none of the Germans are playing chess;
      (10) Whenever some of the English are singing "Rule
         Britannia", and some of the Monitors are asleep,
         some of the Irish are not fighting;
      (11) Whenever some of the Monitors are awake, and
         some of the Eleven are not oiling their bats, some of
         the Scotch are dancing reels;
      (12) Whenever some of the English are singing "Rule
         Britannia", and some of the Scotch are not dancing
         reels, * * * *
  Here the MS. breaks off suddenly.  The Problem is to
complete the sentence, if possible.
  [N.B.  In solving this Problem, it is necessary to remember
that the Proposition "All x are y" is a Double Proposition,
and is equivalent to "Some x are y, and none are y'."