Philosophy of Language: Wittgenstein
Fall 2001
handout on On Certainty
Professor Boedeker
The Tractatus
In the Tractatus, Wittgenstein distinguished between two different kinds of propositions:
1. propositions with sense, which are true in some possible situations, and false in others.
2. propositions without sense, i.e., senseless propositions, which are either
a. tautologies, which are true for every possible combination of truth-value
assignments to their base propositions.
b. contradictions: the negations of tautologies.
It only makes sense to say that someone knows (1) propositions with sense, and not (2) senseless
tautologies (4.461, 5.1362).
Furthermore, only tautologies are certain (4.464, 5.525). This is not because of a speaker’s
subjective, psychological state, but rather because tautologies cannot be false; they are
necessarily true.
Whether a proposition has or lacks sense depends on the form of its base proposition, i.e., the
ranges of their possible truth-value assignments. (See the handout on the Tractatus on sense,
reference, and form.)
The form of a proposition’s base propositions is shown in the rows of its truth-table, by each row
representing a possible combination of truth-value assignments to its bases, and by all the rows
representing just the possible combinations of truth-value assignments to its bases.
On Certainty
In On Certainty, Wittgenstein distinguishes between two different kinds of utterances, i.e.,
assertions of a proposition by a person in a context:
1. empirical hypotheses
2. frame propositions that hold fast for me; also called “hinge”, or “axis”, propositions.
(Virtually all of the propositions canvassed by G.E. Moore in his essays “A Defense of
Common Sense” and “Proof of an External World” are examples of such propositions:
“Here is one hand”, “I have a body”, “I have never been far from the surface of the
earth”, “The earth is at least 100 years old”, etc.)
As in the Tractatus, it only makes sense to say that someone knows (1) empirical hypotheses, not
(2) frame propositions.
Unlike the parallel distinction in the Tractatus, however, this is not a distinction among kinds of
propositions. In fact, the very same proposition might be an empirical hypothesis as uttered by
one person in one context; whereas it might be a frame proposition when uttered by a person
(either the same or different) in another context. One reason for this is that Wittgenstein in On
Certainty counts as frame propositions some of what the Tractatus would count as propositions
with sense. (In fact, all of the propositions canvassed by G.E. Moore in his essays are
propositions with sense in the terms of the Tractatus.)
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In On Certainty, Wittgenstein expands his view of language beyond the merely semantic
dimension (in which the meaning of an expression is just its contribution to the truth-conditions
of propositions in which it occurs) to the pragmatic dimension, i.e., that having to do with doing
things with words beyond merely using them to state facts.
A “linguistic phenomenology” of claims to know
Wittgenstein’s analysis focuses on the pragmatics of knowledge-claims. That is, he describes the
“language-game” in which we use the phrases “I know”, “you know”, “s/he knows”, etc. In so
doing, Wittgenstein breaks with the whole tradition of epistemology. Traditional epistemology
(and mainstream epistemology as practiced today) defines “knowledge” as appropriately
justified true belief, and assumes that appropriate justification is some special relation between a
mind, or subject S, and a proposition p. Traditional epistemology assumes that this relation can
be defined, and attempts to define it. (For some examples, Plato thought that justification is a
matter of a soul’s intuiting Forms. Descartes held that justification is a matter of a thinking
substance’s “clearly and distinctly” perceiving an idea in the mind. Modern “coherentists” hold
something like the view that someone S is justified in believing a proposition p if p is consistent
with a sufficient number of S’s other beliefs. Etc., etc.) In merely restricting his remarks to our
use of claims to knowledge, Wittgenstein refuses to play the game of traditional epistemology.
That is, he is not committed to holding that “knowledge” refers to any particular definable
relation between a mind and a proposition. In general, Wittgenstein thinks that traditional
epistemological problems, such as skepticism, arise because we “reify” (i.e., try to make into a
thing) our talk of knowledge by assuming that knowledge is a thing with an essence. An actual
“linguistic phenomenology” of the use of our claims to know demonstrates that traditional
epistemology is predicated on a misunderstanding of our use of words.
Here is an important basic observation about the pragmatics of knowledge-claims:
When someone S in a given context C claims to know some proposition p, S commits him- or
herself to
a. responding with reasons that are good in C to objections that are relevant in C to S’s
claim to know p
and
b. abandoning the claim to know p if S cannot meet condition (a).
(Note that no such commitments are made when someone simply expresses his or her personal
beliefs, including those of which they are subjectively certain. Religious beliefs might be an
example of such subjective certainties.)
The social context of argumentation determines what counts as a good reason and a relevant
objection under normal conditions. In holding this view, Wittgenstein holds a contextualist view
of justification. Note that several different social contexts of argumentation may be in play at the
same time, and that the same speaker might be involved in different contexts at different times.
For example, surely different standards of justification operate in everyday discourse, scientific
journals, examinations for awarding academic degrees, etc.
The social context of argumentation also determines the difference between (1) empirical
hypothesis and (2) frame propositions that hold fast. (In this way, the social context of
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argumentation plays an analogous role to logical form in the Tractatus.) That is, empirical
hypotheses are ones to which the social context of argumentation permits relevant objections
under normal conditions. For this reason, it makes sense for someone to doubt an empirical
hypothesis, since s/he may have a relevant objection to the hypothesis. Also for this reason, it
makes sense for someone to claim to know an empirical hypothesis, since one can make good on
one’s commitment to respond with good reasons to relevant objections.
Frame propositions that hold fast, on the other hand, are ones to which the social context of
argumentation permits no relevant objections under normal conditions. Frame propositions
are those that persons are entitled to believe without justification. For this reason, it does not
make sense to doubt a frame proposition unless one also has a reason to doubt that the conditions
are not normal. Similarly, it does not make sense under normal conditions to claim to know such
a proposition, since it would not be possible to make good on one’s commitment to respond to
relevant objections to it; after all, there are no good objections to frame propositions under
normal conditions. (This is the basis of Wittgenstein’s criticism of Moore’s defense of common
sense by proving the existence of the external world. Moore wrongly assumed that it did make
sense under normal conditions to claim to know frame propositions.)
Like tautologies in the Tractatus, frame propositions are objectively, not subjectively, certain.
This is because whether or not a proposition is a frame proposition has nothing to do with
whether or not an individual happens to be sure of it. Rather, it is a matter of the social context
of argumentation. Furthermore, just as the Tractatus maintains that logical form shown in a
truth-table, so too is the social context of argumentation shown in which propositions persons in
a given context take as certain frame propositions, as empirical hypotheses, as relevant
objections, or as good reasons.
To see how this works, imagine someone who claims that a frame proposition is false without
giving a good reason to believe that the conditions are not normal. It would be perfectly right to
question whether such a person actually understands the meanings of the words s/he is using.
After all, we teach the meanings of words to someone by uttering frame propositions (although
not by claiming to know them). What better way is there to get someone to understand what
“hand” means than by pointing to a hand and saying “Here is one hand”? Or how else should we
explain what “physical object” means but by pointing to various physical objects and saying
“This is a physical object”? (Wittgenstein calls such statements used in teaching ostensive
definitions.) In this way, someone must believe such frame propositions under normal conditions
in order to have mastered the meanings of the terms involved. Since no one can express a doubt
using words whose meanings s/he does not understand, we have no reason to take seriously
someone’s apparent doubt of a frame proposition without having a good reason to believe that
the conditions are not normal.
How to turn a frame proposition into an empirical hypothesis
Now if Wittgenstein held that the social context of argumentation were something absolutely
fixed and impervious to criticism, then it would be possible to accuse him of relativism (in which
we would have good reason to believe that neither of two competing contexts of argumentation
contained any more truth than the other). It is true that Wittgenstein’s initial response to the
skeptic in ##1-65 of On Certainty seems to leave him open to the threat of relativism. This
response is based on claiming that the proposition accepted by both skeptic and realist – that if
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we know that here is one hand and here is another, then we know that physical objects exist – is
just nonsense. This is because both the propositions “here is one hand and here is another” and
“physical objects exist” are frame propositions, and it is not appropriate to claim either to know
or to doubt frame propositions under normal circumstances. But after all, the relativist can
argue, people in the past have held many frame propositions that have turned out to be false (e.g.,
that the earth was flat, that the earth was at the center of the universe, etc.). Thus what reason do
we have to think that we are in any better position now? In other words, Wittgenstein’s initial
response to the skeptic looks somewhat dogmatic. To see how we can modify this response into
a subtler one that avoids the relativist’s charge of dogmatism, let us first examine two examples
of how there can be reasons to change what counts as a frame proposition in a given context.
The tie shop:* Imagine a client of a tie shop asking to purchase a green tie. The clerk sells the
client a tie that appears to be green. When the client takes the tie into the light of day, however,
the client realizes that the tie really is blue. It only appeared to be green in the tie shop because
of strange yellow lighting. Naturally, the client will demand a refund or an exchange. When he
does so, the clerk is at first entitled simply to repeat his claim that the tie is green. After all,
persons with normal perceptual systems who know the meaning of color terms are entitled to
make claims about colors without further justification – under normal perceptual conditions.
Such beliefs about colors are frame propositions. The problem is that the conditions are not
normal. What the client needs to do is to give a good reason to believe that the conditions in the
tie shop are not normal. To this end, the client can point out the yellow filters on the lights, have
the clerk bring several ties from the shop out into the light of day, and so on. Once the clerk
concedes that the conditions are not normal, he has thereby also conceded that his belief that the
tie is green is not a frame proposition (to which there can be no relevant objections), but rather
an empirical hypothesis (to which there can be relevant objections). At this point, the clerk
theoretically has two options. First, he could abandon his belief that the tie is green, and simply
admit that the client is right in saying that it’s blue. Second, however, particularly stubborn clerk
might claim to know that the tie is green, even though the conditions in the shop are not normal.
It’s difficult to see how this second option could be successful, however, since in claiming to
know that it’s green he commits himself to giving good reasons against relevant objections – and
the strange yellow lighting of the shop is certainly a good objection to the claim to know that the
tie is green.
Scientific revolutions: Thomas Kuhn (in his 1962 book, The Structure of Scientific Revolutions)
has given the title “scientific revolutions” to major shifts in scientific “paradigm”, which
includes the basic concepts and methods of a science. (Examples of scientific revolutions
include the Copernican revolution in astronomy, the overthrow of Aristotelian physics by
Newton, Darwin’s theory of evolution in biology, Einstein’s theory of relativity in physics, and
the introduction of quantum physics.) Put in Wittgensteinian terms, a scientific paradigm is a
social context of argumentation that defines a particular scientific discipline at a given time. A
scientific revolution is opposed to what Kuhn calls “normal science”, which characterizes the
activity of the great majority of scientists. In normal science, scientists work within the accepted
“paradigm” for doing science, and solve particular problems, or puzzles, that come up within that
paradigm. (An example of normal science would be adding new epicycles to the Ptolemaic, or
geocentric, system of astronomy that was dominant through 1500.)
*
This example is borrowed from Wilfrid Sellars’ 1956 essay “Empiricism and the Philosophy of Mind”.
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Let’s assume that a major goal of science is to have theories that account well for the important
observational data. (We need the caveat “important” because there are always some, usually
fairly insignificant, observational data that a paradigm cannot account for well.) This goal
allows us to distinguish periods in which a scientific paradigm is functioning under normal
conditions from periods in which these conditions are abnormal. Note that here, unlike the tie
shop example given above, the relevant conditions of normalcy or abnormality are not
perceptual conditions, but rather the conditions of the social context of argumentation itself (i.e.,
the scientific paradigm). Let us say that a scientific paradigm is functioning under normal
conditions just in case its theories account well for the important observational data. Meeting
this goal is what makes normal science normal. In normal science, the paradigm’s basic theories
are frame propositions. That is, they are beliefs that scientists are entitled to believe without
further justification.
For Kuhn, the transition from normal science to a scientific revolution is always preceded by a
crisis. A scientific paradigm is in crisis just in case there are important observational data that
the paradigm cannot account for well. (Kuhn calls such data “anomalies”.) That is, a scientific
paradigm is in crisis just in case it is functioning under abnormal conditions. In pointing out
important observational data that the paradigm’s theories cannot account for well, someone
thereby offers a good reason that the paradigm is not functioning under normal conditions. This
is analogous to the client in the tie shop example pointing out that the perceptual conditions in
the shop are not normal. When the client points this out, the clerk’s belief that the tie is green
changes from being a frame proposition to being an empirical hypothesis. Similarly, pointing
out that a scientific context of argumentation is not normal changes the paradigm’s basic theories
from frame propositions into empirical hypotheses. This sets the stage for being able to make
objections to these basic theories that are relevant within the current social context of
argumentation. In times of scientific crisis, the current social context of argumentation actually
allows for relevant objections to aspects of itself. One such relevant objection to a basic theory is
that they can account for important observational data only by adding ad hoc theories, i.e.,
theories lacking any principled reason. (The Ptolemaic practice of adding epicycles within
epicycles is a good example of an ad hoc theory.)
For Kuhn, a scientific crisis is resolved by a scientific revolution, in which a new paradigm is
proposed whose basic theories can account for the observational data better than the basic
theories of the old paradigm. Once the new paradigm is accepted, its basic theories become
frame propositions, i.e., propositions that its practitioners are entitled to believe without
justification under normal conditions. Certain basic theories of the old paradigm, namely the
ones that are contradicted by those of the new paradigm, become the opposite of frame
propositions (analogous to contradictions in the Tractatus), i.e., propositions that the
practitioners of the new paradigm are entitled under normal conditions to reject without
justification.
There is an important difference between the case of the tie shop and the scientific revolution. In
the case of the tie shop, the social context of argumentation remains unchanged, but abnormal
perceptual conditions make what would have been a frame proposition into an empirical
hypothesis to which there can now be relevant objections. In the case of the scientific revolution,
however, the abnormal conditions of the social context of argumentation make the basic theories
of that very social context of argumentation itself, which were formerly frame propositions, into
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empirical hypotheses. In a period of crisis, scientists are therefore able to make relevant
objections to the basic theories of their paradigm.
Relativism or skepticism revisited: A relativist or skeptic claims that we do not know that (all
or some) frame propositions in a given social context of argumentation are true, and concludes
from this that we are not entitled to believe them. Note, however, how different this relativistic
or skeptical claim is from that of the client in the tie shop or the proponent of a scientific
revolution. As we have seen, the client does not begin by objecting to the clerk’s claim to know
that the tie is green. For the clerk had not in fact claimed to know this; rather, he was merely
asserting what he took to be a frame proposition. Instead, the client begins by pointing out that
the perceptual conditions are not normal. Only once the abnormality of the conditions in the tie
shop has been pointed out can the clerk’s claim that the tie is green become a knowledge-claim,
and not merely the assertion of a frame proposition. And only then can the client make a
relevant objection to the claim. Similarly, the proponent of a scientific revolution does not begin
by objecting to someone’s claim to know that the basic theories of a scientific paradigm are true.
For since such theories are simply frame propositions in normal science, it would not have been
legitimate for anyone to claim to know them. Instead, the proponent of the new paradigm begins
by pointing out that the conditions of the old paradigm have become abnormal, since the basic
theories of the old paradigm cannot account well for important observational data. Only once the
abnormality of the social context of argumentation itself has been pointed out in this way can
there be relevant objections to its basic theories.
The problem with the relativist or skeptic is that s/he has skipped the necessary first step in
challenging our entitlement to frame propositions. That is, s/he has given no good reasons to
believe that conditions are not normal. We would be perfectly justified in concluding that such a
person either is crazy or does not understand the meanings of his or her words. Or, more likely,
the relativist or skeptic has a faulty conception of knowledge – mistaking it for some relation
(that of “appropriate justification”) of a mind to a proposition, which s/he can then argue is
absent in the case of frame propositions. But such a conception ignores the pragmatics of actual
claims to knowledge – both in everyday and scientific contexts. Someone can legitimately claim
to know only those propositions to which the social context of argumentation allows relevant
objections. And, as we have seen, someone can legitimately doubt a proposition only if (1) it is
an empirical hypothesis under normal conditions, or (2) that person has a good reason to believe
that the conditions are not normal. Relativistic or skeptical doubts – including those based on the
fact that frame propositions of past social contexts of argumentation have been false – meet
neither of these conditions for legitimate doubt. This would seem to be the most adequate
response to relativism or skepticism by a contextualist view of justification.
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