  The Description Theory of Quotation was introduced in order to guarantee that ‘a quoted series of expressions is always a series of quoted expressions’ (Geach 1957, p. 82) and not ‘a single long word, whose parts have no separate significance’ (ibid., p. 82). According to this theory, there is a set of basic units in each language: words, according to Geach (ibid., Ch. 18 and 1970); letters, according to Tarski (1956, p. 160) and Quine (1960, p. 143, p.  212)).[6]