A presupposition trigger is a lexical item or linguistic construction which is responsible for the presupposition, and thus "triggers" it. The following is a selection of presuppositional triggers following
Stephen C. Levinson's classic textbook on
Pragmatics, which in turn draws on a list produced by
Lauri Karttunen. As is customary, the presuppositional triggers themselves are italicized, and the symbol » stands for 'presupposes'.
Definite descriptions Definite descriptions are phrases of the form "the X" where X represents a noun phrase. The description is said to be
proper when the phrase applies to exactly one object, and conversely, it is said to be
improper when either there exist more than one potential referents, as in "the senator from Ohio", or none at all, as in "the king of France". In conventional speech, definite descriptions are implicitly assumed to be proper, hence such phrases trigger the presupposition that the referent is unique and existent. • John saw
the man with two heads. »there exists a man with two heads.
Factive verbs In Western epistemology, there is a tradition originating with
Plato of defining knowledge as justified true belief. On this definition, for someone to know X, it is required that X be true. A linguistic question thus arises regarding the usage of such phrases: does a person who states "John knows X" implicitly claim the truth of X?
Steven Pinker explored this question in a
popular science format in a 2007 book on language and cognition, using a widely publicized example from a speech by a U.S. president. A 2003 speech by George W. Bush included the line, "British Intelligence has learned that Saddam Hussein recently sought significant quantities of uranium from Africa." Over the next few years, it became apparent that this intelligence lead was incorrect. But the way the speech was phrased, using a factive verb, implicitly framed the lead as truth rather than hypothesis. There is however a strong alternative view that the
factivity thesis, the proposition that relational predicates having to do with knowledge, such as
knows, learn, remembers, and
realized, presuppose the factual truth of their object, is incorrect. • Martha
regrets drinking John's home brew. • Presupposition: Martha did in fact drink John's home brew. • Frankenstein was
aware that Dracula was there. • Presupposition: Dracula was in fact there. • John
realized that he was in debt. • Presupposition: John was in fact in debt. • It was
odd how proud he was. • Presupposition: He was in fact proud. Some further factive predicates:
know; be sorry that; be proud that; be indifferent that; be glad that; be sad that. Implicative verbs • John
managed to open the door.»John tried to open the door. • John
forgot to lock the door.»John ought to have locked, or intended to lock, the door. Some further implicative predicates:
X happened to V»X didn't plan or intend to
V;
X avoided Ving»X was expected to, or usually did, or ought to
V, etc.
Change of state or continuation of state verbs With these presupposition triggers, the current unfolding situation is considered presupposed information. • John
stopped teasing his wife.»John had been teasing his wife. • Joan
began teasing her husband.»Joan hadn't been teasing her husband. Some further change of state verbs:
start; finish; carry on; cease; take (as in
X took Y from Z » Y was at/in/with Z);
leave; enter; come; go; arrive; etc.
Iteratives These types of triggers presuppose the existence of a previous state of affairs. • The flying saucer came
again.»The flying saucer came before. • You can't get gobstoppers
anymore.»You once could get gobstoppers. • Carter
returned to power.»Carter held power before. Further iteratives:
another time; to come back; restore; repeat; for the nth time. Temporal clauses The situation explained in a clause that begins with a temporal clause constructor is typically considered backgrounded information. •
Before Strawson was even born, Frege noticed presuppositions.»Strawson was born. •
While Chomsky was revolutionizing linguistics, the rest of social science was asleep.»Chomsky was revolutionizing linguistics. •
Since Churchill died, we've lacked a leader.»Churchill died. Further temporal clause constructors:
after; during; whenever; as (as in
As John was getting up, he slipped).
Cleft sentences Cleft sentence structures highlight particular aspects of a sentence and consider the surrounding information to be backgrounded knowledge. These sentences are typically not spoken to strangers, but rather to addressees who are aware of the ongoing situation. •
Cleft construction: It was Henry that kissed Rosie.»Someone kissed Rosie. •
Pseudo-cleft construction: What John lost was his wallet.»John lost something.
Comparisons and contrasts Comparisons and contrasts may be marked by stress (or by other prosodic means), by particles like "too", or by comparatives constructions. • Marianne called Adolph a male chauvinist, and then
HE insulted
HER.»For Marianne to call Adolph a male chauvinist would be to insult him. • Carol
is a better linguist than Barbara.»Barbara is a linguist.
Counterfactual conditionals •
If the notice
had only
said 'mine-field' in Welsh as well as in English, we
would never
have lost poor Llewellyn.»The notice didn't say 'mine-field' in Welsh.
Questions Questions often presuppose what the assertive part of the question presupposes, but interrogative parts might introduce further presuppositions. There are
three different types of questions: yes/no questions, alternative questions and WH-questions. •
Is there a professor of linguistics at MIT?»Either there is a professor of linguistics at MIT or there isn't. •
Is Newcastle in England
or in Australia?»Newcastle is in England or Newcastle is in Australia. •
Who is the professor of linguistics at MIT?»Someone is the professor of linguistics at MIT.
Possessive case • John'
s children are very noisy.»John has children. ==Accommodation of presuppositions==