Limits of pl Example Consider a simple sentence, every student is younger than some instructor olution It is a declarative statement which can be expressed by a proposition letter, say P ema O However, it means being a students, being a instructor and being younger than somebody else o P fails to reflect the finer logic structure of it May9,201212/22Limits of PL Example Consider a simple sentence, every student is younger than some instructor. Solution It is a declarative statement, which can be expressed by a proposition letter, say P. Remark 1 However, it means being a students, being a instructor and being younger than somebody else. 2 P fails to reflect the finer logic structure of it. Yi Li (Fudan University) Discrete Mathematics May 9, 2012 12 / 22