Ideas of Hilary Putnam, by Theme

[American, b.1926, Taught at Princeton, then MIT, then Professor at Harvard University.]

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1. Philosophy / A. Wisdom / 1. Nature of Wisdom
For ancient Greeks being wise was an ethical value
1. Philosophy / D. Nature of Philosophy / 4. Aims of Philosophy / a. Philosophy as worldly
The job of the philosopher is to distinguish facts about the world from conventions
1. Philosophy / G. Scientific Philosophy / 1. Aims of Science
Realism is the only philosophy of science that doesn't make the success of science a miracle
1. Philosophy / G. Scientific Philosophy / 3. Scientism
A culture needs to admit that knowledge is more extensive than just 'science'
'True' and 'refers' cannot be made scientically precise, but are fundamental to science
3. Truth / A. Truth Problems / 1. Truth
'The rug is green' might be warrantedly assertible even though the rug is not green
Putnam's epistemic notion of truth replaces the realism of correspondence with ontological relativism
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
We need the correspondence theory of truth to understand language and science
Before Kant, all philosophers had a correspondence theory of truth
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Correspondence between concepts and unconceptualised reality is impossible
The correspondence theory is wrong, because there is no one correspondence between reality and fact
3. Truth / E. Pragmatic Truth / 1. Pragmatic Truth
Truth is an idealisation of rational acceptability
Truth is rational acceptability
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
For scientific purposes there is a precise concept of 'true-in-L', using set theory
3. Truth / F. Semantic Truth / 2. Semantic Truth
Only Tarski has found a way to define 'true'
Semantic notions do not occur in Tarski's definitions, but assessing their correctness involves translation
In Tarski's definition, you understand 'true' if you accept the notions of the object language
Tarski has given a correct account of the formal logic of 'true', but there is more to the concept
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Asserting the truth of an indexical statement is not the same as uttering the statement
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
Modern notation frees us from Aristotle's restriction of only using two class-names in premises
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
The universal syllogism is now expressed as the transitivity of subclasses
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC
'⊃' ('if...then') is used with the definition 'Px ⊃ Qx' is short for '¬(Px & ¬Qx)'
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
In type theory, 'x ∈ y' is well defined only if x and y are of the appropriate type
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
We understand some statements about all sets
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
Gödel proved the classical relative consistency of the axiom V = L
The Löwenheim-Skolem theorems show that whether all sets are constructible is indeterminate
V = L just says all sets are constructible
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Before the late 19th century logic was trivialised by not dealing with relations
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Asserting first-order validity implicitly involves second-order reference to classes
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Unfashionably, I think logic has an empirical foundation
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Putnam coined the term 'if-thenism'
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
We can identify functions with certain sets - or identify sets with certain functions
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
Using proper names properly doesn't involve necessary and sufficient conditions
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Having a valid form doesn't ensure truth, as it may be meaningless
5. Theory of Logic / I. Semantics of Logic / 6. Intensionalism
Intension is not meaning, as 'cube' and 'square-faced polyhedron' are intensionally the same
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
If cats equal cherries, model theory allows reinterpretation of the whole language preserving truth
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
The Löwenheim-Skolem Theorem is close to an antinomy in philosophy of language
6. Mathematics / A. Nature of Mathematics / 4. The Infinite / f. Uncountable infinities
Sets larger than the continuum should be studied in an 'if-then' spirit
6. Mathematics / A. Nature of Mathematics / 4. The Infinite / j. Large cardinals
Very large sets should be studied in an 'if-then' spirit
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
I do not believe mathematics either has or needs 'foundations'
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Number / a. Axioms for numbers
It is conceivable that the axioms of arithmetic or propositional logic might be changed
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
How can you contemplate Platonic entities without causal transactions with them?
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Maybe mathematics is empirical in that we could try to change it
It is unfashionable, but most mathematical intuitions come from nature
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Science requires more than consistency of mathematics
Indispensability strongly supports predicative sets, and somewhat supports impredicative sets
We must quantify over numbers for science; but that commits us to their existence
7. Existence / D. Theories of Reality / 1. Realism
Realists believe truth is correspondence, independent of humans, is bivalent, and is unique
Metaphysical realism is committed to there being one ultimate true theory
Realism is a theory, which explains the convergence of science and the success of language
7. Existence / D. Theories of Reality / 3. Anti-realism
It is an illusion to think there could be one good scientific theory of reality
You can't deny a hypothesis a truth-value simply because we may never know it!
If we try to cure the abundance of theories with causal links, this is 'just more theory'
The sentence 'A cat is on a mat' remains always true when 'cat' means cherry and 'mat' means tree
7. Existence / D. Theories of Reality / 7. Facts / a. Facts
A fact is simply what it is rational to accept
8. Modes of Existence / B. Properties / 12. Denial of Properties
Very nominalistic philosophers deny properties, though scientists accept them
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
Nominalism only makes sense if it is materialist
9. Objects / A. Existence of Objects / 1. Physical Objects
Aristotle says an object (e.g. a lamp) has identity if its parts stay together when it is moved
9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta
Physics is full of non-physical entities, such as space-vectors
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
Shape is essential relative to 'statue', but not essential relative to 'clay'
9. Objects / D. Essence of Objects / 5. Essence as Kind
Putnam bases essences on 'same kind', but same kinds may not share properties
9. Objects / D. Essence of Objects / 15. Against Essentialism
Putnam smuggles essentialism about liquids into his proof that water must be H2O
10. Modality / A. Necessity / 11. Denial of Necessity
If necessity is always relative to a description in a language, then there is only 'de dicto' necessity
10. Modality / B. Possibility / 1. Possibility
Mathematics eliminates possibility, as being simultaneous actuality in sets
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
A statement can be metaphysically necessary and epistemologically contingent
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
Conceivability is no proof of possibility
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Saying that natural kinds are 'rigid designators' is the same as saying they are 'indexical'
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
If a tautology is immune from revision, why would that make it true?
12. Knowledge Sources / B. Perception / 4. Sense Data / b. Nature of sense-data
The old view that sense data are independent of mind is quite dotty
13. Knowledge Criteria / C. External Justification / 7. Testimony
Knowledge depends on believing others, which must be innate, as inferences are not strong enough
Empathy may not give knowledge, but it can give plausibility or right opinion
13. Knowledge Criteria / E. Relativism / 6. Relativism Critique
Some kind of objective 'rightness' is a presupposition of thought itself
14. Science / A. Basis of Science / 4. Prediction
Most predictions are uninteresting, and are only sought in order to confirm a theory
14. Science / B. Scientific Theories / 2. Aim of Science
Science aims at truth, not at 'simplicity'
14. Science / B. Scientific Theories / 3. Instrumentalism
Naïve operationalism would have meanings change every time the tests change
14. Science / D. Explanation / 4. Explanation Doubts / a. Explanation as pragmatic
You can't decide which explanations are good if you don't attend to the interest-relative aspects
17. Mind and Body / B. Behaviourism / 2. Potential Behaviour
Dispositions need mental terms to define them
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
Superactors and superspartans count against behaviourism
Total paralysis would mean that there were mental states but no behaviour at all
17. Mind and Body / C. Functionalism / 1. Functionalism
Is pain a functional state of a complete organism?
Functionalism is compatible with dualism, as pure mind could perform the functions
Functional states correlate with AND explain pain behaviour
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
Instances of pain are physical tokens, but the nature of pain is more abstract
Functionalism says robots and people are the same at one level of abstraction
17. Mind and Body / C. Functionalism / 8. Functionalism critique
If concepts have external meaning, computational states won't explain psychology
Functionalism can't explain reference and truth, which are needed for logic
Is there just one computational state for each specific belief?
17. Mind and Body / D. Property Dualism / 3. Property Dualism
Temperature is mean molecular kinetic energy, but they are two different concepts
17. Mind and Body / E. Mind as Physical / 3. Eliminativism
If we are going to eliminate folk psychology, we must also eliminate folk logic
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability
If humans and molluscs both feel pain, it can't be a single biological state
18. Thought / A. Modes of Thought / 5. Folk Psychology
Can we give a scientific, computational account of folk psychology?
18. Thought / A. Modes of Thought / 6. Rationality
Rationality is one part of our conception of human flourishing
18. Thought / B. Mechanics of Thought / 4. Language of Thought
If everything uses mentalese, ALL concepts must be innate!
No machine language can express generalisations
18. Thought / C. Content / 5. Twin Earth
If Twins talking about 'water' and 'XYZ' have different thoughts but identical heads, then thoughts aren't in the head
We say ice and steam are different forms of water, but not that they are different forms of H2O
Does 'water' mean a particular substance that was 'dubbed'?
'Water' on Twin Earth doesn't refer to water, but no mental difference can account for this
Reference may be different while mental representation is the same
18. Thought / C. Content / 6. Broad Content
I can't distinguish elm trees, but I mean by 'elm' the same set of trees as everybody else
'Water' has an unnoticed indexical component, referring to stuff around here
Reference is social not individual, because we defer to experts when referring to elm trees
18. Thought / D. Concepts / 3. Ontology of Concepts / b. Concepts as abilities
Concepts are (at least in part) abilities and not occurrences
19. Language / A. Nature of Meaning / 1. Meaning
Meaning and translation (which are needed to define truth) both presuppose the notion of reference
Theory of meaning presupposes theory of understanding and reference
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Truth conditions can't explain understanding a sentence, because that in turn needs explanation
We should reject the view that truth is prior to meaning
19. Language / A. Nature of Meaning / 6. Meaning as Use
"Meaning is use" is not a definition of meaning
19. Language / A. Nature of Meaning / 7. Meaning Holism / b. Lanugage holism
Holism seems to make fixed definition more or less impossible
Meaning holism tried to show that you can't get fixed meanings built out of observation terms
Understanding a sentence involves background knowledge and can't be done in isolation
19. Language / C. Reference / 1. Reference theories
How reference is specified is not what reference is
19. Language / C. Reference / 3. Direct Reference / a. Direct reference
We should separate how the reference of 'gold' is fixed from its conceptual content
Like names, natural kind terms have their meaning fixed by extension and reference
19. Language / C. Reference / 3. Direct Reference / b. Causal reference
I now think reference by the tests of experts is a special case of being causally connected
19. Language / C. Reference / 3. Direct Reference / c. Social reference
Reference (say to 'elms') is a social phenomenon which we can leave to experts
Neither individual nor community mental states fix reference
We need to recognise the contribution of society and of the world in determining reference
Maybe the total mental state of a language community fixes the reference of a term
Aristotle implies that we have the complete concepts of a language in our heads, but we don't
19. Language / C. Reference / 4. Descriptive Reference / a. Sense and reference
Often reference determines sense, and not (as Frege thought) vice versa
19. Language / C. Reference / 4. Descriptive Reference / b. Reference by description
The claim that scientific terms are incommensurable can be blocked if scientific terms are not descriptions
19. Language / F. Communication / 4. Private Language
Language is more like a cooperative steamship than an individual hammer
A private language could work with reference and beliefs, and wouldn't need meaning
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
The correct translation is the one that explains the speaker's behaviour
Language maps the world in many ways (because it maps onto other languages in many ways)
There are infinitely many interpretations of a sentence which can all seem to be 'correct'
19. Language / F. Communication / 6. Interpreting Language / c. Principle of charity
You can't say 'most speaker's beliefs are true'; in some areas this is not so, and you can't count beliefs
22. Metaethics / A. Value / 1. Nature of Value / f. Fact and value
The word 'inconsiderate' nicely shows the blurring of facts and values
26. Natural Theory / B. Concepts of Nature / 6. Natural Kinds / d. Source of kinds
The hidden structure of a natural kind determines membership in all possible worlds
26. Natural Theory / B. Concepts of Nature / 6. Natural Kinds / f. Reference to natural kinds
Express natural kinds as a posteriori predicate connections, not as singular terms
"Water" is a natural kind term, but "H2O" is a description
Natural kind stereotypes are 'strong' (obvious, like tiger) or 'weak' (obscure, like molybdenum)
26. Natural Theory / C. Causation / 2. Particular Causation / d. Selecting the cause
An alien might think oxygen was the main cause of a forest fire
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
If causes are the essence of diseases, then disease is an example of a relational essence
Archimedes meant by 'gold' the hidden structure or essence of the stuff
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
If water is H2O in the actual world, there is no possible world where it isn't H2O