  Even the sentences of Frege’s mature logical system are (complex) denoting terms; they are terms that denote truth-values. Frege distinguished two truth-values, The True and The False, which he took to be objects. The basic sentences of Frege’s system are constructed using the expression ‘\((\:) = (\:)\)’, which signifies a binary function that maps a pair of objects x and y to The True if x is identical to y and maps x and y to The False otherwise. A sentence such as ‘\(2^2 = 4\)’ therefore denotes the truth-value The True, while the sentence ‘\(2^2 = 6\)’ denotes The False.