In the previous module
we saw some semantic properties of presuppositions—most importantly, the
fact that they are unaffected by negation. But we oversimplified a bit; in fact,
linguists have recognized for several decades now that it's quite difficult to
accurately describe how all presuppositions behave. A wide variety of sentence
structures trigger presuppositions (some were illustrated in one of the discussion
activities for the previous module), and they do not all behave the same way;
for instance, as we saw in one of the discussions, certain kinds of questions
seem to trigger presuppositions but their presuppositions actually are affected
by negation. These problems have led some linguists to argue that presuppositions
are actually a pragmatic phenomenon, rather than a purely structural linguistic/semantic
phenomenon, and therefore we need to explain them via pragmatic principles—
in other words, we can't explain them purely by making reference to how they
behave in various semantic tests, but we have to think about what people intend
when they use presuppositions.
In that module we also had a brief preview of a concept that
forms the foundation of that explanation, the idea of "backgroundedness". As
we discussed in that module, presuppositions tend to convey information "in the
background", rather than as the main focus of the utterance. Now we will need
to think more specifically about what that actually means. To have a more formal
explanation of this concept, we will first need to explain what is meant by
the "background", and then think about how presuppositions are related to it. Let's
tackle those two issues one by one.
The common ground
When people talk to each other, their is a lot of shared context
between them. If you and I are standing in the cafeteria talking, I know where
we are and I can (usually) assume that you also know where we are, and that
we both know certain things about what cafeterias are, what people do there,
etc. We might also know certain information about each other, and all kinds of
other contextual information that might be relevant to our conversation. We
also know what came before in the conversation—for example, if you
ask me "Where's the restroom?", I can just say "Over there"
and I can trust that you will understand that my utterance really means
"The restaurant is over there", because I can trust that you remember the
question you asked right before I made that very short utterance.
The collection of all the background context information that
people in a conversation know is often called the common ground.
More specifically, the common ground is all the information that participants
in the conversation mutually know (i.e. I know that you know, I know
that you know that I know, I know that you know that I know that you know, et
cetera ad infinitum).
The "background" we mentioned above is the same thing as the
"common ground". Now let's see how presuppositions are related to it.
Presuppositions and the common ground
Some people have suggested that presuppositions are simply
information that is already in the common ground when some utterance is
While this definition is on the right track, it's nevertheless
clearly wrong, because we frequently say things that presuppose stuff that's not
in the common ground. For example, imagine I have just met
someone and that person tells me they study graphic design;
I could say "Wow, my brother studied graphic design!"
This utterance presupposes that I have a brother, and that
is not information that's in the common ground (the person
just met me and could not possibly know I have a brother). We
can also use presuppositions to indirectly ask about things
that are not in the common ground yet; for instance, as we
will see later in the modules about indirectness,
when someone wants to know if you have a boyfriend but doesn't
want to ask directly, they might ask something like, "Oh, is
that a text message from your boyfriend?", hoping that
you will say "I don't have a boyfriend"; in this case, the
speaker doesn't know if you have a boyfriend and thus it's
not common-ground information, it's something they want to
ask about (and your relationship status might then get added
into the common ground for the rest of the conversation,
depending on how you respond to their indirect question).
In fact, as other theories have pointed out, presuppositions
are often a way that we can introduce new information
into the common ground without making it our main focus.
The common-ground idea can be rescued (see
Levinson, chapter 4.4) with a small revision. Presuppositions
don't have to be information that is already in the common
ground, but can be information that is consistent with
what's in the common ground. So we could define presuppositions
in the following way: An utterance A presupposes a proposition
B if and only if the utterance A is only appropriate when the
proposition B is consistent with what's in the common ground.
In the "my brother" example above,
it's common knowledge that many people have
brothers, and thus my utterance "My brother studied
graphic design" seems pretty appropriate, because
what it presupposes seems pretty consistent with the common
ground. On the other hand, if I had said, "My hostage studied
graphic design" would be a much weirder thing to say
if the context was a random conversation on the street,
because the idea that most people have hostages is certainly
not part of the common ground!
I'm not sure this really explains what presuppositions
are. It seems more like an explanation of when utterances
are felicitious (it seems more reasonable to say that "My
hostage studied graphic design" has a presupposition which is
infelicious, rather than saying it just doesn't have a presupposition).
Nevertheless, it gets us one step closer to understanding what
presuppositions are, or at least what they're used for and how they
What people do with presuppositions
The above idea about the common ground is
useful for understanding presuppositions, because it helps explain
what presuppositions are used for. As we discussed at the beginning
of this module, many pragmaticists have argued
that an utterance's entailments and implicatures are what the
utterance is really "about", and its presuppositions are information
which we assume in the background but are not what the utterance is
really about. More specifically, for example, Burton-Roberts
(1989), Chapman (2011, chapter 2.7), argues that when a speaker utters something
that has a presupposition, the speaker is presenting the presupposed
information as if it is "not subject to debate" (i.e., it is likely
something that everyone in the conversation will agree with and
accept), whereas the speaker is presenting the explicit literal meaning
as if it is "subject to debate" (i.e., it's the main focus of what
the speaker is conveying, and people might agree or disagree with it).
For example, in the Communist Manifesto, Marx and Engels
famously wrote that "What the bourgeoisie produces, above all, are its own
grave-diggers"; this utterance presupposes that the bourgeoisie
produces something, and it presents that idea as uncontroversial
(indeed, the previous 20 pages or so had all been talking about
the relationship of the bourgeoisie to production—and then, more
specifically, how the bourgeoisie creates the proletariat), whereas
what it explicitly says is that the things it produces are its
own grave-diggers (which really means, pragmatically and metaphorically,
that what the bourgeoisie produces—the proletariat—is the
same thing that will eventually destroy the bourgeoisie). Importantly,
this latter bit is presented as a novel insight, rather than a piece
of background information that is already accepted; accordingly, in
the almost 200 years since the publication of the Manifesto,
there has been a lot of debate
over whether Marx and Engels's claim was right or not. Importantly,
no one disagrees with the idea that the bourgeoisie produces something,
but lots of people disagree with the idea that the proletariat will
destroy the bourgeoisie; in other words, no one disagrees with the
presupposition of their utterance, but lots of people disagree with
Of course, we must keep in mind that the things people's
utterances presuppose might not always really be uncontroversial. People
sometimes presuppose controversial things. Sometimes this can even be
a sneaky way for people to try to get people to accept their idea without
noticing it. A classic example is asking a question like "Have you
stopped smoking?", which presupposes that the person used to smoke.
No matter whether the person says "yes" or "no", they will look like they
are admitting that they used to smoke; the only way to avoid that is for
them to deny the presupposition itself (by saying, e.g., "Your question
doesn't make sense, I never smoked in the first place").
(2019, chapter 6.5-6.6) has an in-depth discussion of a cross-examination
during a legal case, in which the defense lawyer uses a lot of presuppositions
to attempt to undermine the plaintiff's case. Importantly, the reason
presuppositions are sometimes effective for this is precisely because
they are presented in a way to make them seem uncontroversial,
so it might sometimes be tricky to notice that someone is presupposing
an idea that's actually controversial.
This detail about the use of presupposition—i.e.,
the fact that presuppositions present information as being uncontroversial
or not "at issue"—is part of what sets it apart from many other aspects
of meaning. Some pragmaticists have used this observation to argue that
presupposition is a wholly pragmatic phenomenon and not related to semantics
at all, and that we cannot identify and describe presuppositions by their
sentence structures or their susceptibility to tests such as the negation
test described above, but we instead have to recognize presuppositions based
on their pragmatic information status. For the reasons I mentioned above,
I'm still not convinced that we can use this as an effective diagnostic
for presuppositions; whether or not something is uncontroversial can't
accurately tell us it's a presupposition. But considering both the semantic
factors (stuff like susceptibility to negation) and the pragmatic factors
(how people try to make certain claims look like they're uncontroversial
and "in the background") can help us have a full picture of what
presuppositions really are.
Here is a sign I saw in a restroom at my university:
The English says, "Please put the toilet seat cover down before flushing".
The Chinese, on the other hand, says "請蓋上廁板后沖廁"
("Please flush the toilet after closing the cover"; literally, "please after closing the
cover flush the toilet").
While these literally mean the same thing (flushing the toilet after closing the cover
is the same as closing the cover before flushing the toilet), some people might feel
like there is a very subtle difference between what they convey. Does the concept of
presupposition and backgroundedness help explain the difference?