1 Semantik für Realisten. 2 1. Die Welt ist alles was der Fall ist. Das, was nicht der Fall ist,...

Preview:

Citation preview

1

Semantik für Realisten

2

1. Die Welt ist alles was der Fall ist.

Das, was nicht der Fall ist, gehört nicht zur Welt.

3

5.6 Die Grenzen meiner Sprache bedeuten die Grenzen meiner Welt.

Falschheiten (das, was nicht der Fall ist) kann ich in meiner Sprache nicht zum Ausdruck bringen.

4

Wittgensteins Lösung

5

2. Was der Fall ist, die Tatsache, ist das Bestehen von Sachverhalten.

Sachverhalte können also bestehen oder nicht bestehen.

Es gibt also nicht nur die Welt, sondern auch zusätzliche Bereiche (von möglichen Welten, nicht-bestehenden Sachverhalten udgl.)

6

2.01 Der Sachverhalt ist eine Verbindung von Gegenständen (Sachen, Dingen).

Dies gilt eigentlich nur von bestehenden Sachverhalten.

Wie vermeiden wir nicht-bestehende Sachverhalte?

7

Wittgensteins Bildtheorie der Sprache

2.1 Wir machen uns Bilder der Tatsachen.

8

Das propositionale Bild als ein Komplex von Namen

3.14 Das Satzzeichen besteht darin, dass sich seine Elemente, die Wörter, in ihm auf bestimmte Art und Weise voneinander verhalten.  

9

Satz

a r b

4.22 Der Elementarsatz besteht aus Namen.Er ist ein Zusammenhang, eine Verkettung, von Namen.

10

Satz und Sachverhalt

a r b

language

world

names

simple objects

11

Der Satz als Bild eines Sachverhalts

3.21 Der Konfiguration der einfachen Zeichen im Satzzeichen entspricht die Konfiguration der Gegenstände in der Sachlage.

3.22 Der Name vertritt im Satz der Gegenstand.

12

Satz und Sachverhalt

a r b

language

world

projection

13

Die Projektion

3.12 ... der Satz ist das Satzzeichen in seiner projektiven Beziehung zur Welt.

3.13 Zum Satz gehört alles, was zur Projektion gehört; aber nicht das Projizierte.

14

Semantic Projection

„ Blanche is shaking hands with Claire “

Ein Satz

15

A Map

16

Satz und Sachverhalt

a r b

Semantic Projection

„ John kisses Mary “

John this kiss Mary

17

Falsehood

2.21 Das Bild stimmt mit der Wirklichkeit überein oder nicht; es ist richtig oder unrichtig, wahr oder falsch.

18

Satz und Sachverhalt

a r b

Falsehood

„John kisses Mary“

John Maryprojection

fails

19

Falsehood: A Realist Theory

Falsehood is not: successful conformity with some non-existing state of affairs

... it is the failure of an attempted conformity, resting on either

1. failure of projection, or

2. failure of coordination

20

4.25 Ist der Elementarsatz wahr, so besteht der Sachverhalt; ist der Elementarsatz falsch, so besteht der Sachverhalt nicht.

21

Satz und Sachverhalt

a r b

Projection Failure

„John kisses Mary“

John Mary

nothing here

22

Nothing

really nothing

23

Satz und Sachverhalt

a r b

Projection Failure

„John kisses Mary“

John Mary

24

Coordination Failure

a r b„John kisses Mary“

Mary this kiss John

Coordination Failure

25

Realist Semantics

We begin with a theory of propositions as articulated pictures of reality

The theory of truth comes along as a free lunch

We then show how to deal with the two kinds of failure which constitute falsehood

26

Semantic Projection„ Blanche is shaking hands with Claire “

Semantic Projection

27

Optical Projection

28

Cartographic Hooks

Cartographic Projection

29

Semantic ProjectionThe Problem of Vagueness

30

Semantic Projection

„ Blanche is shaking hands with Claire “

The Problem of Vagueness

what is thisentity called ashaking of hands?

31

The Problem of Vagueness

Wittgenstein solved this problem by presupposing that the world is made up of absolute simples and that only in relation to configurations of absolute simples can language picture reality.

Can the semantic realist find a better solution?

32

The basic machinery of realist semantics

33

 

A Simple Partition

34

A partition can be more or less refined

A partition can be more or less refined

35

36

 

37

A partition is transparent

It leaves the world exactly as it is

38

39

Artist’s Grid

40

Label/Address System

A partition typically comes with labels and/or an address or coordinate system

41

Cerebral Cortex

42

Mouse Chromosome Five

43

Partitions are artefacts of our cognition

= of our referring, perceiving, classifying, mapping activity

44

Partitions always have a certain granularity:

when I see an apple my partition does not recognize the molecules in the apple

45

A partition is transparent

= it corresponds to a true propositional picture in the sense of the Tractatus

46

Intentionality

47

Intentionality

48

CartographicHooks

49

an object x is recognized by a partition:

= there is some cell in which x is located

50

The theory of partitionsis a theory of foregrounding,of setting into relief

Cf. L. Talmy, The Windowing of Attention in Language

51

You use the name ‘Mont Blanc’ to refer to a certain mountain

You see Mont Blanc from a distance

In either case your attentions serve to foreground a certain portion of reality

Setting into Relief

52

You use the name ‘Mont Blanc’ to refer to a certain mountain

You see Mont Blanc from a distance

In either case your attentions serve to foreground a certain portion of reality

Setting into Relief

53

You use the name ‘Mont Blanc’ to refer to a certain mountain

You see Mont Blanc from a distance

In either case your attentions serve to foreground a certain portion of reality

Setting into Relief

54

You use the name ‘Mont Blanc’ to refer to a certain mountain

You see Mont Blanc from a distance

In either case your attentions serve to foreground a certain portion of reality

Setting into Relief

55

Hertz

4.04 Am Satz muss gerade soviel zu unterscheiden sein, als an der Sachlage die er darstellt. Die beiden müssen die gleiche logische (mathematische) Mannigfaltigkeit besitzen.

56

Wittgenstein: a sentence can picture a complex in reality only if the two have the same logical-mathematical multiplicity.

Have we solved this problem of logical-mathematical multiplicity?

57

Cartographic Hooks

Cartographic Projection

58

Foreground/Background

our partition does not allow us torecognize objects beneath a certain size

59

Have we solved the problem of logical-mathematical multiplicity?

60

The Problem of the Many

There is no single answer to the question as to what it is to which the term ‘Mont Blanc’ refers. Many parcels of reality are equally deserving of the name ‘Mont Blanc’

– Think of its foothills and glaciers, and the fragments of moistened rock gradually peeling away from its exterior; think of all the rabbits crawling over its surface

61

Mont Blanc from Chatel

62

Mont Blanc (Tricot)

63

The world itself is not vague

Rather, there are for any given referring term different equally good ways to demarcate its referent from out of the surrounding messy reality

64

The world itself is not vague

Rather, many of the terms we use to refer to objects in reality are such that, when we use these terms, we stand to the corresponding parcels of reality in a relation that is one-to-many rather than one-to-one.

65

Many but almost oneDavid Lewis:

There are always outlying particles, questionable parts of things, not definitely included and not definitely not included.

66

Tracing Over

Granularity:

if x is recognized by a partition A, and y is part of x, it does not follow that y is recognized by the partition A.

67

 

John

68

When you think of John on the baseball field, then the cells in John’s arm and the fly next to his ear belong to the portion of the world that does not fall under the beam of your referential searchlight.

They are traced over.

69

 

John

70

Granularity

Cognitive acts of Setting into Relief: the Source of Partitions

Partititions: the Source of Granularity

Granularity: the Source of Vagueness

71

 

John

72

Granularity the source of vagueness

... your partition does not recognize parts beneath a certain size.

This is why your partition is compatible with a range of possible views as to the ultimate constituents of the objects included in its foreground domain

73

Granularity the source of vaguenessIt is the coarse-grainedness of our partitions which allows us to ignore questions as to the lower-level constituents of the objects foregrounded by our uses of singular terms.

This in its turn is what allows such objects to be specified vaguely

Our attentions are focused on those matters which lie above whatever is the pertinent granularity threshold.

74

Reference can be successful even though our referring terms are vague

Satz und Sachverhalta r b

projection

75

Reference can be successful even though our referring terms are vague

Satz und Sachverhalta r b

alternative crisp aggregates of matter

projection is a one-to-many function

76

Bill Clinton is one person

Mont Blanc is one mountain

Consider:

77

these are both trueno matter which of the many aggregates of matter we assign as precisified referent of the corresponding terms

78

Bill Clinton is one person

– both are true on the appropriate level of granularity(our normal, common-sense ontology is in perfect order as it stands)

Mont Blanc is one mountain

79

John is kissing Mary

Blanche is shaking hands with Claire

and the same applies to:

80

The world is messyHow to solve the problem of vagueness?

Supervaluationism:

we need to distinguish between truth and supertruth

81

Definition of precisification

a precisification is an acceptable way of projecting from a term to a crisp aggregate of matter

(to Bill Clinton with these hairs in his ear, to Bill Clinton without those hairs in his ear, and so on)

82

For each term

there is a range of admissible precisified references

(some with bits of hair, some without; some with bits of food, some without)

83

Standard Supervaluationism

A sentence is supertrue if and only if it is true under all precisifications.

A sentence is superfalse if and only if it is false under all precisifications.

A sentence which is true under some ways of precisifying and false under others is said to fall down a supervaluational truth-value gap. Its truth-value is indeterminate.

84

but ...

85

semantic realism has no room for truth-value gaps

4.25 Ist der Elementarsatz wahr, so besteht der Sachverhalt; ist der Elementarsatz falsch, so besteht der Sachverhalt nicht.

86

Mont Blanc (Tricot)look for the rabbits

87

Are those rabbits part of Mont Blanc?

88

Mont Blanc (Tricot)

89

Example of Gaps

On Standard Supervaluationism

Rabbits are part of Mont Blanc

falls down a supertruth-value gap

90

Rabbits

Some precisifications contain rabbits as parts

Some precisifications do not contain rabbits as parts

91

Can we do better?

Well consider that there are different contexts involved

92

In a perceptual context it is supertrue that these rabbits are part of Mont Blanc

In a normal context of explicit assertion it is superfalse that these rabbits are part of Mont Blanc

In a real estate context in a hunting community it is supertrue that these rabbits are part of that mountain

93

The hunter says: These rabbits are

part of my mountain

94

But now, if we stick to some one given context, then even with

Rabbits are part of Mont Blanc,

there are no gaps.

95

Hypothesis:

projection always within some given context

there are no naturallyoccurring contexts with gaps

96

Supervaluationism Contextualized

We pay attention in different ways and to different things in different contexts

So: the range of available precisified referents is dependent on context.

97

Supervaluationism Contextualized

Thus the evaluations of supervaluationism should be applied not to sentences taken in the abstract but to judgments taken in their concrete real-world contexts

98

No gaps

The everyday judgments made in everyday contexts do not fall down supervaluational truth-value gaps

This is so, because the sentences which might serve as vehicles for such judgments are in normal contexts not judgeable

99

Unjudgeability

Consider:

Rabbits are part of Mont Blanc

is in the normal contexts occupied by you and me unjudgeable

100

Normal contexts

(including normal institutional contexts) have immune systems which protect them against problematic utterances

such utterances are not taken seriously as expressing judgments

101

Judgments and Evolution

Most naturally occurring contexts possess immune systems because those which did not would have been eliminated in the struggle for survival.

102

Contextualized Supervaluationism

A judgment p is supertrue if and only if:

• (T1) the judgment successfully projects, in its context C, upon corresponding families of precisifications, and

• (T2) the corresponding families of precisifications are such that p is true whichever precisification we select.

103

Supertruth and superfalsehood are not symmetrical:

A judgment p is superfalse if and only if

either:

• (F0) it fails to project, in its context C, upon anything in the world corresponding to its constituent singular referring terms,

104

Falsehoodor both:

• (F1) the judgment successfully projects, in its context C, upon corresponding families of precisifications, and

• (F2) the corresponding families of precisifications are such that p is false whichever precisification we select.

105

Pragmatic presupposition failure:

In case (F0), p fails to reach the starting gate for purposes of supervaluation

Consider: „Karol Wojtyła is more intelligent than the present Pope“

106

Lake Constance

No international treaty establishes where the borders of Switzerland, Germany, and Austria in or around Lake Constance lie.

• Switzerland takes the view that the border runs through the middle of the Lake.

• Austria and Germany take the view that all three countries have shared sovereignty over the whole Lake.

107

Lake Constance

If you buy a ticket to cross the lake by ferry in a Swiss railway station your ticket will take you only as far as the Swiss border (= only as far as the middle of the lake)

108

but for all normal contextsconcerning

fishing rights,

taxation,

shipping,

death at sea, etc., there are treaties regulating how decisions are to be made (with built in immune-systems guarding against problematic utterances)

109

Lake Constance

an ontological black hole in the middle of Europe

110

Lake Constance (D, CH, A)

SwitzerlandAustria

Germany

111

That Water is in Switzerland

You point to a certain kilometer-wide volume of water in the center of the Lake, and you assert:

[Q] That water is in Switzerland.

Does [Q] assert a truth on some precisifications and a falsehood on others?

112

No

By criterion (F0) above, [Q] is simply (super)false.

Whoever uses [Q] to make a judgment in the context of currently operative international law is making the same sort of radical mistake as is someone who judges that Karol Wojtyła is more intelligent than the present Pope.

113

Reaching the Starting Gate

In both cases reality is not such as to sustain a partition of the needed sort.

The relevant judgment does not even reach the starting gate as concerns our ability to evaluate its truth and falsehood via assignments of specific portions of reality to its constituent singular terms.

114

Partitions do not care

Our ordinary judgments, including our ordinary scientific judgments, have determinate truth-values

because the partitions they impose upon reality do not care about the small (molecule-sized) differences between different precisified referents.

115

No Gaps

‘Bald’, ‘cat’, ‘dead’, ‘mountain’ are all vague

But corresponding (normal) judgments nonetheless have determinate truth-values.

There are (on one way of precisifying ‘normal’ in the above) no truth-value gaps

116

The philosophical contexts invented by philosophers interested in the logic of vagueness are not normal

117

DOWN

WITH

PHILOSOPHY !

118

THE END

THE END

Recommended