This document introduces the formal language of propositional logic. It defines the basic alphabet which includes propositional symbols, logical constants, and connectives. Propositional symbols represent propositions that can be true or false. Logical constants represent truth values. Connectives represent logical relations between propositions. Well-formed formulas are defined as strings of symbols from the alphabet that follow certain syntactic rules. The document notes some limitations of only using propositional logic to represent natural languages, which contain more semantic elements.
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