'The practices and positions of an activity are also realised in texts. A text is an utterance or set or sequence of utterances made within the context of one or more activities. The empirical object of analysis of the present work is a school mathematics scheme. This scheme consists of a set of utterances of the activity school mathematics. The chapters that follow are concerned with the analysis of these utterances and not with the interactions between them and what may occur in a classroom within which they are used nor, indeed, with what happens when an empirical reader takes up the texts. Thus, the empirical text is being constituted as monologic. All texts construct authors and readers; a monologic text constructs a single author and so can be read in relation to a single activity. All texts (re)produce, in part, the practices of the activity (or activities) of which they are utterances. Pedagogic texts, which are my immediate concern, construct authors as transmitters and readers as acquirers. The transmitter is in possession of the regulative principles of the practices of the activity which the acquirer is to acquire. Transmitter and acquirer are textual constructions which are textual realisations of positions. The practices and positions of an activity are thus instantiated in pedagogic texts. The instantiation of practices will be referred to as message; the instantiation of positions will be referred to as voices.'

(Dowling, 1998; p. 131)