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Transcript
KNOWLEDGE
What is it?
 How does it differ from
belief?
 What is the relationship
between knowledge and
truth?
These are the concerns
of epistemology




How do we acquire it?
What is its scope – how
far does it extend?
Is it necessary to be able
to convince someone
else that what I claim as
an item of knowledge is
more than mere belief?
Knowledge
Definitions (1)
[1] How about knowledge as something more
certain than mere belief? When we are in an
infallible state of mind?
But, there are counter-instances where despite
being convinced we are later shown to be
wrong by newly emerging facts.
Should we therefore ground knowledge in
objective reality not subjective belief?
You can always count on a Greek
for a point of view in philosophy
 And
usually this
is PLATO
Knowledge
Definitions (2)
[2] Have knowledge and belief different objects?
Plato at one point held something like this.
Later he seems to say that to know something
is to believe it and provide an adequate
account – an analysis or definition of essential
features.
So, is knowledge equal to belief plus
understanding?
Mind you, Plato isn’t the only top
Greek philosopher
 There
is always
Aristotle if you
are looking for a
second opinion
Knowledge
Definitions (3)


Whereas Plato seemed not to be interested in
justification or certainty, Aristotle perhaps was.
Aristotle (uncritically) recognised the given of
sense-data and the notion of causes as
certain. Knowledge of a particular thing
presupposes a quest for an explanation or
‘ultimate’ cause.
Knowledge
Definitions (4)


A.J. Ayer (1910-89) holds along with many
modern philosophers that knowledge and belief
have the same objects.
His definition:
Knowledge is justified true belief.
TRUTH
theories about truth

Several views are current on the issue of
‘Pilate’s question’

PRAGMATIC THEORY
COHERENCE THEORY
CORRESPONDANCE THEORY
REDUNDANCY THEORY



PRAGMATISM



US philosophers Charles Pierce (1839-1914) &
William James (1842-1910).
“True ideas are those that we can assimilate,
validate, corroborate and verify. False ideas
are those we cannot.” - James
“it is useful because it is true….it is true
because it is useful” - James
American pragmatists were all the
rage at the turn of the century
This is Charles
Sanders Pierce
 You should be
aware too of the
importance of
John Dewey and
of William James

Mind you, not everyone was a fan
of pragmatism

For example our
own, our very
own, Bertrand
Russell.
PRAGMATISM
objections
Many of these made by Bertrand Russell:
 The notion of ‘works for me/us’ is ambiguous.
 In everyday discourse we distinguish between
‘useful’ & ‘truth’. James is redefining these
terms in his identification of one with the other.
 ‘Working for us’ is problematic because it is
almost impossible to determine the
consequences of holding a particular belief.
Back in the 19th cc Idealists were all
the rage

One of the top
men was the
unique figure of
George Hegel
whose writings are
not always
transparent!
COHERENCE
by 18th&19th cc idealists
such as G.W.F.Hegel & F.H.Bradley.
 A statement is true if it ‘coheres’ or
‘fits in’ with other statements thereby
forming a complete system.
 Advocated
COHERENCE
Critical remarks




There is more than one possible coherent system.
Coherence requires the notion of logical
consistency which in turn requires the notion of
logically prior truth and falsity (as more than
defined by coherence theory).
Internally coherent systems cannot say anything
about the relation of the system to the world.
COHERENCE MAY BE A TEST OF TRUTH BUT
IT CANNOT TELL US WHAT TRUTH MEANS.
CORRESPONDANCE
1
Russell argued that any theory of truth must
satisfy these three criteria:
[1] It must admit of its opposite - falsehood.
[2] Truth and falsity must be properties of beliefs
and statements.
[3] These properties depend on the relation of
these statements to something outside those
beliefs.

CORRESPONDANCE
2


If a belief is true it must correspond to a fact of
some kind which ‘exists’ in the world.
One objection is that it is the meaning of
statements or beliefs which count, and this is
what a proposition (p) is. Propositions rather
than beliefs carry truth or falsity. I should say “p
is true and I believe it” rather than “I believe p”.
CORRESPONDANCE
3


This view entails the need to be very specific
with propositions to avoid the charge that p can
sometimes be true and sometimes false.
The second difficulty is in the question, ‘Can
propositions be distinguished from the facts
that they are supposed to correspond to, and if
so, how?’ ie. How do we get outside of our
language? cf. Wittgenstein.
Wittgenstein is viewed by many as
the greatest 20th cc philosopher

Encouraged by
Russell to get stuck
into philosophy at
Cambridge, he was
later to eclipse the
old man, who
reacted, it is
rumoured, with a
touch of jealousy!
CORRESPONDANCE
4

An objection to Russell’s account (Problems of
Philosophy XII) is that propositions have a
funny sort of existence between ourselves and
the supposed ‘outside world’. Might not a true
proposition be a fact itself? Why the distinction,
which is needed if the correspondance is
possible? What is meant by ‘objective
existence’ here?
CORRESPONDANCE
5


According to Russell there is a correspondance
between a belief and a fact when (a) there is a
complex unity of object terms and an object
relation, and (b) when the order of these terms
and relations is ‘in the same order as they have
in the belief’. The judgement having a ‘sense’
or ‘direction’.
How do we get outside our language?
REDUNDANCY
1



Originally proposed by F.P. Ramsay and later
modified by P.F. Strawson. Utilises what
J.L.Austin called ‘performatives’. Hence in
Strawson it is the Performatory theory.
We make the notion of truth redundant by
saying that when we say that x is true, we do
no more than to say that we agree to accept x.
Will this do? How do we know what to accept?