Describir: IMPLICATION, formalisation et logique naturelle /

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 | \| ||  /_   _//  \ \\/ // | || | ||  /_   _//  |  ___||   ____     |  ___|| 
 |  ' ||   -| ||-    \   //  | || | ||  `-| |,-   | ||__    |    \\   | ||__   
 | .  ||   _| ||_    / . \\  | \\_/ ||    | ||    | ||__    | [] ||   | ||__   
 |_|\_||  /_____//  /_//\_\\  \____//     |_||    |_____||  |  __//   |_____|| 
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