 We take the language of Classical propositional logic \(\bCPL\) to be the set \(L_c = \{\wedge , \vee , \rightarrow , \top , \bot \},\) where \(\wedge , \vee , \rightarrow\) are binary connectives and \(\top , \bot\) propositional constants. We assume that the consequence relation is defined by the usual truth-table method \((\top\) is interpreted as true and \(\bot\) as false) as follows,