Russell’s theory of descriptions
Inés Crespo
NYUParis & IJN
inescrespo@gmail.com
17 February 2016
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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Plan for today
Discussion
What’s next?
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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General remarks
• Ontological worries: non existent concreta. This results from
an epistemological positition: direct realism. If we can have
knowledge of the world as it really is, then our knowledge of
the world must not be mediated.
• Another form of anti-psychologism, but one for which Frege’s
epistemology amounts to a form of idealism.
• K by acquaintance and and K by description. R’s commitment
with empiricism.
• Underlying idea of language: for R, language is a system of
representation for the things and states (and possible states)
of the world; for F, language is an externalization of, and thus
a system for representing, thought.
• As with Frege, in OD natural language appears as being
misleading. Grammatical form vs. logical form.
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PHILUA-85 Spring 2016 | Session 10
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Discussion
• Denoting phrases:
– Quantified phrases
– Indefinite descriptions
– Definite descriptions
• Acquaintance and K about. All K starts with acquaintance.
We have K of certain objects by description.
• The theory (a reductive theory):
C(x) is a propositional function. [like a property]
Basic: “C(x) is always true”; “C(x) is sometimes true”.
C (everything) means “C(x) is always true”.
C (nothing) means “ ‘C(x) is false’ is always true”.
C (something) means “It is false that ‘C(x) is false’ is always true”.
• The principle: denoting phrases do not have any meaning by
themselves.
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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Discussion (cont.1)
• “C (a man)” means “ ‘C(x) and x is a human’ is not always
false”. (N.B.: here man is used as synonym of human being,
not of male.)
• “All men are mortal” means “ ‘If x is a human, x is mortal’ is
always true”.
The general case is: “C (all men)” means “ ‘If x is human,
then C(x) is true’ is always true”. [The same analysis applies
to “C (every man)”.]
• “C (no men)” means “ ‘If x is human, then C(x) is false’ is
always true”.
• “C (a man)” means “It is false that ‘C(x) and x is human’ is
always false”. [The same analysis applies to “C (some men)”.]
• The case of definite descriptions is the most interesting and
difficult.
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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Discussion (cont.2)
• When strictly used, the implies uniqueness. E.g., “the son of
Philip II of Macedon” and “a son of Philip II of Macedon”.
“the father of Charles II” means “x begat Charles II; and ‘if y begat Charles II, y is
identical with x’ is always true of y”.
We eliminate or reduce definite descriptions by expanding
them into complex existential statements.
• When you insert this denoting phrase in a proposition, you get:
“The father of Charles II was executed” means “It is not always false of x that x
begat Charles II; and that x was executed; and ‘if y begat Charles II, y is identical
with x’ is always true of y”.
• More generally, you can say: “C (the father of Charles II)”
means “It is not always false of x that x begat Charles II; and
that x meets C; and ‘if y begat Charles II, y is identical with
x’ is always true of y”.
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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What’s next?
Session 11: Mon, 22 Feb.
Topic: Wrap up Russell (1905). Prep. for the mid-term exam.
Your task: think of questions in preparation of the mid-term exam.
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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Contact
• E-mail: inescrespo@gmail.com, ic40@nyu.edu
• Office hours: Mondays from 14h00 till 15h00, room 506.
• Course webpage: http://inescrespo.altervista.org/nyu.html
Inés Crespo | NYUParis & IJN
PHILUA-85 Spring 2016 | Session 10
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