Implicature is a strand of pragmatics that attempts to deal with how context affects the meaning of what we say. Much work in the field posits the existence of 'pragmatic principles' which we use in order to interpret what people say. Grice's 'co-operative principle' (1975) is a particularly influential concept here. The principle consists of four 'maxims' which describe how we are able to use language to communicate effectively with one another. These maxims do not seek to dictate how we should talk, but rather are default expectations which, it is argued, must exist in order for our talk to be understandable:
• Quantity — provide a suitable amount of information, neither too much nor too little.
• Quality — say only what you believe to be true, and only that for which you have evidence.
• Relation — be relevant.
• Manner — do not be obscure or ambiguous, but brief and orderly.
Speakers or writers do not need to constantly abide by the four maxims in order for hearers or readers to understand their contributions. In fact, deviation from the maxims allows us to create meaning in ways we could not if we rigidly stuck to them. Often, when someone does 'flout' one or more of the maxims — for example, by saying something that they are aware is not literally true — we realise that they are deliberately deviating from the maxims, and that they must be trying to communicate a message that could not be found in a literal reading of what they have said. For example, the popular conception that 'Tony Blair is George Bush's lapdog' during Blair's time as British prime minister did not express a literal truth, but encouraged the audience to think of ways in which Blair could be seen to be similar to a lapdog: servile, meek, fawning. By flouting the maxim of quality, the use of this metaphor allowed people to describe Blair in a creative way. Likewise, a friend who tells us that 'I love it when you forget to do the washing-up' is probably flouting the maxim of quality in order to make a point about our sloppiness when it comes to household chores.
The following exchange is taken from a 2012 interview on the UK daytime TV programme This Morning. In the interview, presenter Philip Schofield confronted David Cameron about the action the government had been perceived (not) to be taking in relation to scandals involving the media, government and paedophilia:
Schofield (handing piece of paper to Cameron): You know the names on that piece of paper. Will you be speaking to those people?
Cameron: Look I think Philip this is really important, right, because there is a danger — if we're not careful, that this could turn into a sort of, err, a sort of witch-hunt.
Firstly, it is worth noting that Schofield's question itself seems to carry an implicature: if Schofield is handing the list to Cameron, and asking him about his plans regarding it, the maxim of relevance would suggest that Schofield is implying that Cameron ought to speak to "those people".
Cameron's response appears to flout the Gricean maxim of relevance, as it does not directly answer Schofield's question: we might surmise that Cameron is trying to say 'No, I will not be speaking to those people'. Relatedly, Cameron could also be seen to be flouting the maxim of quantity — the question he was asked requires only a 'yes' or 'no' answer, but his response is much longer than this. Further, consideration of the Gricean maxims can help us interpret other parts of Cameron's response. By recourse to the maxim of relevance, we may conclude that when Cameron says "if we are not careful... this could turn into a witch-hunt" in response to Schofield's proffering of the list of names, he is indirectly scolding Schofield for actions that might be deemed crass or rash: while he uses 'we', the fact that he is in conversation with Schofield suggests that he is primarily addressing Schofield.
Presuppositions are the assumptions that we make any time we speak or write. They can be divided into two main types: existential and logical. Existential presuppositions occur constantly in language and are pivotal in allowing us to talk about the world around us: by simply using a noun phrase like 'the trouble in Palestine' or 'the terrorist group Al Qaida', we are assuming that a reader or listener will accept that such things exist. This process of 'reification' — the way in which the contents of a noun phrase are portrayed as a real thing — can be used by speakers or writers to refer to contentious things as though they were real and incontestable. For example, a conspiracy theorist might refer to 'the inside job of 9/11' in order to present as concrete something that many would see as being a mere theory.
• The lying, murderous Tony Blair refused to apologise.
• Tony Blair is a liar and murderer, and refused to apologise.
In the first sentence, Tony Blair's apparent disingenuousness and murderousness are hard to contest because 'lying' and 'murderous' are part of the same noun phrase as 'Tony Blair'. It would be easier to argue that 'no, he isn't a liar and murderer' in the case of the second sentence, in which the qualities attributed to Blair are the actual proposition of the sentence.
Logical presuppositions are caused by a variety of different triggers. Below is an outline of the most common of these, with examples to demonstrate how they work:
• Change of state verbs presuppose an earlier state of affairs by stating that something has changed — 'the Allies stopped their bombing campaign in Libya' (they were bombing in Libya before), 'the Conservatives started to think about a plan B for the economy' (they weren't thinking about one before).
• Factive verbs presuppose the truthfulness of the information that follows them — 'the Conservatives understand that the economy is in crisis', 'Labour knows that its record in office was dire'.
• Iterative words hint that something must have occurred more than once — 'Blair refused to apologise again' (he must have refused to apologise at least once before), 'the UN has reinvigorated its bombing campaign' (the bombing campaign must have already been underway in order for it to be reinvigorated).
The use of triggers is of great significance in texts produced by powerful speakers or writers, as they allow them to confidently paint a picture of the world as they see it whilst also making their portrayal hard to contest.
Perhaps the simplest type of presupposition or implicature to spot is existential presupposition. While ubiquitous, they can also be extremely effective. Think of the discussion of the threat posed by Saddam Hussein in the build-up to the second Iraq war: while there are still considerable question marks over whether Hussein did ever have access to weapons of mass destruction, the fact that they were presented in noun phrases like 'Saddam's weapons of mass destruction' by politicians meant that they were presented to the public as something definite and real. When watching or reading the news, think carefully about the noun phrases that are used, and the information that is presented as simply 'real' and 'existing' in this way.
'Implying and assuming' in Jeffries' guide to critical stylistic tools explains how implicature and presupposition can have powerful ideological effects:
Jeffries, Lesley. 2010. Critical Stylistics: The Power of English. Hampshire: Palgrave Macmillan, 93-105.
Levinson's book offers a thorough account of how presupposition and implicature work:
Levinson, Steven C. 1993. Pragmatics. Cambridge: Cambridge University Press.
Simpson and Mayr demonstrate the usefulness of the analysis of presupposition in forensic discourse analysis in their book's section on 'Developments in forensic discourse analysis':
Simpson, Paul and Andrea Mayr. 2010. Language and Power: A Resource Book for Students. Oxon: Routledge, 81-85.