description of presupposition and Entailment

1. Semantics
PRESENTATION TOPIC: ENTAILMENT
AND PRESUPPOSITION

2. Entailment
Entailment is something that
logically follows from what is
asserted in the utterance.
Entailment is sentence based

3. Entailment Relations And Truth
Conditions:
 Either S1 entails S2 or S2 entails S1 i.e., truth
conditionally related
 Neither S1 entails S2 nor S2 entails S1 , i.e.,
truth conditionally unrelated
 Both S1 and S2 entails each other i.e., truth
conditionally equivalent.
 Both S1and S2 contradicts each other i.e.,
truth conditionally contradicted.

4. Presupposition
Presupposition is something the
speakers assume to be the case prior
to making an utterance.
Two Approaches to presupposition
 semantic approach
Pragmatic approach

5. For Example
p) John’s brother has just got back
from Texas.
q) John has a brother.

6. Presupposition as a truth relation
o if p (the presupposing sentence) is
true then q (the presupposed
sentence) is true.
o If p is false , then q is still true.
o If q is true , p could either be true or
false.

7. o For example :
p) John’s brother has just got back
from Texas.
q) John has a brother.

8. Presupposition failure
For example
a. The king of France is bald.
b. there is a king of France.

9. Presupposition Triggers
 Presuppositions are produced by
particular words or constructions,
called presupposition triggers.
 Many of the lexical triggers are verbs
i.e.,
 Factive verbs
 Aspectual verbs

10. Factive verbs like realize , regret etc.
a) John regretted eating the banana.
b) John considered eating the
banana.
c) John ate banana.

11. Aspectual verbs like start , begin ,
stop.
a)John started smoking.
b) John used not to smoke.

12. Pragmatic theories of
presupposition
 Stalnaker argued that presupposition is
essentially a pragmetics phenomenon.
 Sperber and Wilson argued that
presupposition is not an independent
phenomenon but one of a series of effects
produced when the speaker employs
syntactic structure and intonation to show
the hearer how the current sentence fits
into previous background.

13. Example
Do YOU like it?
Do you LIKE it?
Do you like IT?

14. Thank you…