Deixis and Presupposition

The phenomenon of deixis fixes the utterance in the physical (temporal and spatial deixis, see Reference, 5.1.1) and social (social deixis, which includes  person deixis and  attitudinal deixis, see also 9.1) context of its use. Deixis, which may also be used ´self-referentially´ to point to itself (discourse deixis, see Endophoric reference, 5.1.1), is realized by  indexical (deictic) expressions, such as personal and possessive pronouns,  adverbials, verbal categories of person and tense, but also by politeness and phatic formulae. Presupposition represents the amount of information assumed to be known by participants (background knowledge, common ground) and has direct impact on how much is explicitly said and how much remains implicit. Since it is normally not necessary, let alone possible, to be fully explicit, a certain level of balance is strived for by the participants who take into consideration various factors (see 3.2); for example, the medium of writing tends to be more explicit as participants do not share the time and space, often an unknown (general) addressee is projected with whom the amount of the shared knowledge can only be estimated.