2 Frege's Puzzles; Sense vs. Reference

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2Frege's Puzzles Sense vs. Reference
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Teaching Assistants

• Brenden MURPHY
• bjmurphy_at_connect.carleton.ca
• office h 1200-100pm
• Paterson 330A
• Mark TOVEY
• mtovey_at_connect.carleton.ca
• office h

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Identity

• Its a relation (a b), but
• 1. between objects?
• 2. between signs (i.e. names of objects)?

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• If its a relation between objects then
• a b doesnt differ from a a
• We would say that an object is identical to
  itself.

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• If its a relation between signs then
• given that signs are arbitrary we would lose
  contact with what the signs stand for (the
  subject matter) and, again, a b would not
  differ from a a.
• It would amount of saying that the word a is
  identical to the word b.

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Cognitive Value

• a b and a a (e.g. Superman is Superman
  vs. Superman is Clark Kent) differ in cognitive
  value.
• If a b merely concerns the objects a and b,
  its cognitive content would not differ from the
  one of a a.
• All we would know is that an object is identical
  with itself.

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• If a b merely concerns the signs a and b,
  its cognitive content would not differ from the
  one of a a.
• All we would know is that signs a and b are
  identical.
• It seems that identity is neither a relation
  between objects, nor a relation between signs
  (nouns/names).

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Formulating Freges Problem

• Terminology
• n a referring expression e.g. Tully
• r(n) r is the referent of n e.g.
  Tully(Tully)

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• S? a sentence containing the singular term ?
  e.g. Tully smokes is a sentence containing the
  singular term Tully
• S?/? a sentence obtained by replacing the
  occurrences of ? with occurrences of ? e.g.
  Jane smokes can be obtained by replacing
  occurrences of Tully with occurrence of Jane
  in Tully smokes

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• Substitution Principle (Begriffsschrift)
• If S? is about r(?), then if r(?) r(?),
• S? and S?/? have the same cognitive value.
• if Tully smokes is about the referent of
  Tully then, if the referent of Tully the
  referent of Cicero , Tully smokes and Cicero
  smokes have the same cognitive value

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• 2 Assumptions
• 1. Substitution principle
• 2. Identity relates objects
• These two assumptions generate the following
  paradox
• a b differs in cognitive value from a a,
  yet, according to the substitution principle they
  do not differ.

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• Solution
• reject either (1) or (2),
• i.e. either the substitution principle or the
  view that identity relates objects.

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• Solution 1 Early Frege (Begriffsshrift 1879)
• Rejection of assumption 2
• Identity is not a relation between objects (its
  a relation between signs).

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• Solution 2 Later Frege
• (Über Sinn und Bedeutung / Sense and
  Reference 1892)
• The sense/reference solution.
• Rejection of assumption 1, i.e. the substitution
  principle.

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• Substitution of coreferential singular terms
  preserves truth value but not cognitive value.
• In substituting terms with the same sense
  cognitive value is preserved .

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Freges Puzzles

• Cognitive value
• Hesperus Hesperus is trivial and
  non-informative, whereas Hesperus Phosphorus
  is informative.
• So, the cognitive value of these sentences
  ought to differ. Where does the difference come
  in?

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• Freges solution
• Hesperus and Phosphorus express two distinct
  senses (Sinne),
• I.e. the modes of presentations of the referent
  (Bedeutung), i.e. Venus, associated with both
  terms are different.

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Proper Names

• A proper name expresses a sense and refers to an
  object.
• The sense of a proper name, say Tully, is the
  mode of presentation of the object, Tully, it
  stands for. Intuitively, a sense is that property
  of a linguistic expression in virtue of which it
  is understood (grasped) by a competent speaker.

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• Sense and thought
• The sense of a sentence (thought) is determined
  by the senses of its constituents.
• Different senses make different contributions to
  a thought.

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Sense vs. Reference

• Sense determines reference
• r(n) r(s)n))
• e.g. the referent of Tully is the referent of
  the sense of Tully

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• Reference is a function
• Any two terms having the same sense refer to the
  same object, i.e.
• If s(n) s(m), then r(n) r(m)

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Freges Semantics

• Three worlds
• 1. Language
• 2. World of senses/thoughts
• 3. Reality

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• 1. sign proper name predicate
  sentence
• ? ? ?
  ?
• 2. sense/thought sense sense
  thought
• ? ? ?
  ?
• 3. referent object concept
  Truth Value
• 
  
• ? object falling
  
  
  under the
  concept

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• A proper names is a linguistic expression which
• (i) expresses a sense and
• (ii) stands for/refers to/designates an object.
• An object is the ontological reflection of a name.

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• Sentences are compound proper names whose
  referents are either the Truth or the False which
  are objects.
• The Bedeutung of a sentence (the truth value) is
  determined by the Bedeutung of its constituents,
  just as the sense of a sentence (the thought
  expressed) is determined by the senses of its
  constituents.

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Oratio Obliqua

• Oratio obliqua vs oratio recta i.e indirect
  discourse vs direct discourse intensional
  contexts vs extensional context
• (1) Sue believes that Hesperus is a star
• (2) Hesperus Phosphorus
• So (3) Sue believes that Phosphorus is a star
• How to block this inference, i.e. the
  substitution salva veritate of Hesperus and
  Phosphorus?

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Freges Solution

• (i) Hesperus and Phosphorus express different
  senses
• (ii) Senses are the constituents of thoughts
  (Gedanke),

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• (iii) an attitude ascription relates a subject
  with a thought
• So (iv) (1) and (3) do not relate Sue with the
  same thought and, therefore, may differ in truth
  value.
• The moral is that the names Hesperus and
  Phosphorus cannot be substituted salva veritate
  in oratio obliqua constructions.

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Ordinary Senses vs. Indirect Senses

• The ordinary sense is what is referred to, via an
  indirect sense, by embedded expressions.
• Since embedded expressions switch reference,
  Frege gives up semantic innocence.
• E.g. Hesperus in (1) and Phosphorus in (3)
  do not refer to Venus, but to their ordinary
  sense, which differ.

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• (1) gets represented as
• (1a) BEL (Sue, ltMP(Hesperus), MP(being a
  star)gt)
• while (3) as
• (1b) BEL (Sue, lt MP(Phosphorus), MP(being a
  star)gt)

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• MP(Hespeus) differs from MP(Phosphorus)
• Thus as (1a) and (3a) show, (1) and (3) do not
  relate Sue with the same thought.
• Thus, they may well differ in truth value.

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• Moral
• Coreferring expressions / terms / names cannot
  be substituted salva veitate in oblique / oratio
  obliqua / intensional contexts.