Combining Texts

All the ideas for 'The Evolution of Logic', 'Possible Worlds' and 'The Elm and the Expert'

unexpand these ideas     |    start again     |     specify just one area for these texts


76 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / c. Eighteenth century philosophy
We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD]
     Full Idea: We are all post-Kantians, ...because Kant set an agenda for philosophy that we are still working through.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Hart says that the main agenda is set by Kant's desire to defend the principle of sufficient reason against Hume's attack on causation. I would take it more generally to be the assessment of metaphysics, and of a priori knowledge.
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / d. Philosophy as puzzles
The problems are the monuments of philosophy [Hart,WD]
     Full Idea: The real monuments of philosophy are its problems.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Presumably he means '....rather than its solutions'. No other subject would be very happy with that sort of claim. Compare Idea 8243. A complaint against analytic philosophy is that it has achieved no consensus at all.
1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
To study abstract problems, some knowledge of set theory is essential [Hart,WD]
     Full Idea: By now, no education in abstract pursuits is adequate without some familiarity with sets.
     From: William D. Hart (The Evolution of Logic [2010], 10)
     A reaction: A heart-sinking observation for those who aspire to study metaphysics and modality. The question is, what will count as 'some' familiarity? Are only professional logicians now allowed to be proper philosophers?
2. Reason / A. Nature of Reason / 8. Naturalising Reason
A standard naturalist view is realist, externalist, and computationalist, and believes in rationality [Fodor]
     Full Idea: There seems to be an emerging naturalist consensus that is Realist in ontology and epistemology, externalist in semantics, and computationalist in cognitive psychology, which nicely allows us to retain our understanding of ourselves as rational creatures.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
3. Truth / A. Truth Problems / 5. Truth Bearers
Psychology has to include the idea that mental processes are typically truth-preserving [Fodor]
     Full Idea: A psychology that can't make sense of such facts as that mental processes are typically truth-preserving is ipso facto dead in the water.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §1.3)
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD]
     Full Idea: It is an ancient and honourable view that truth is correspondence to fact; Tarski showed us how to do without facts here.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: This is a very interesting spin on Tarski, who certainly seems to endorse the correspondence theory, even while apparently inventing a new 'semantic' theory of truth. It is controversial how far Tarski's theory really is a 'correspondence' theory.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD]
     Full Idea: We explain truth for sentences in terms of satisfaction of formulae. The crux here is that for a sentence, either all sequences satisfy it or none do (with no middle ground). For formulae, some sequences may satisfy it and others not.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: This is the hardest part of Tarski's theory of truth to grasp.
3. Truth / F. Semantic Truth / 2. Semantic Truth
A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD]
     Full Idea: In any first-order language, there are infinitely many T-sentences. Since definitions should be finite, the agglomeration of all the T-sentences is not a definition of truth.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: This may be a warning shot aimed at Davidson's extensive use of Tarski's formal account in his own views on meaning in natural language.
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD]
     Full Idea: A 'conditional proof' licenses inferences to a conditional from a deduction of its consequent from its antecedent.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: That is, a proof can be enshrined in an arrow.
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD]
     Full Idea: When a quantifier is attached to a variable, as in '∃(y)....', then it should be read as 'There exists an individual, call it y, such that....'. One should not read it as 'There exists a y such that...', which would attach predicate to quantifier.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: The point is to make clear that in classical logic the predicates attach to the objects, and not to some formal component like a quantifier.
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Set theory articulates the concept of order (through relations) [Hart,WD]
     Full Idea: It is set theory, and more specifically the theory of relations, that articulates order.
     From: William D. Hart (The Evolution of Logic [2010])
     A reaction: It would seem that we mainly need set theory in order to talk accurately about order, and about infinity. The two come together in the study of the ordinal numbers.
Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD]
     Full Idea: The theory of types is a thing of the past. There is now nothing to choose between ZFC and NBG (Neumann-Bernays-Gödel). NF (Quine's) is a more specialized taste, but is a place to look if you want the universe.
     From: William D. Hart (The Evolution of Logic [2010], 3)
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
∈ relates across layers, while ⊆ relates within layers [Hart,WD]
     Full Idea: ∈ relates across layers (Plato is a member of his unit set and the set of people), while ⊆ relates within layers (the singleton of Plato is a subset of the set of people). This distinction only became clear in the 19th century.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: Getting these two clear may be the most important distinction needed to understand how set theory works.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD]
     Full Idea: Without the empty set, disjoint sets would have no intersection, and we could not form a∩b without checking that a and b meet. This is an example of the utility of the empty set.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: A novice might plausibly ask why there should be an intersection for every pair of sets, if they have nothing in common except for containing this little puff of nothingness. But then what do novices know?
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
In the modern view, foundation is the heart of the way to do set theory [Hart,WD]
     Full Idea: In the second half of the twentieth century there emerged the opinion that foundation is the heart of the way to do set theory.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: It is foundation which is the central axiom of the iterative conception of sets, where each level of sets is built on previous levels, and they are all 'well-founded'.
Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD]
     Full Idea: The usual statement of Foundation is that any nonempty set has a member disjoint from it. This phrasing is ordinal-free and closer to the primitives of ZFC.
     From: William D. Hart (The Evolution of Logic [2010], 3)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD]
     Full Idea: When a set is finite, we can prove it has a choice function (∀x x∈A → f(x)∈A), but we need an axiom when A is infinite and the members opaque. From infinite shoes we can pick a left one, but from socks we need the axiom of choice.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: The socks example in from Russell 1919:126.
With the Axiom of Choice every set can be well-ordered [Hart,WD]
     Full Idea: It follows from the Axiom of Choice that every set can be well-ordered.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: For 'well-ordered' see Idea 13460. Every set can be ordered with a least member.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD]
     Full Idea: It has been said (by Burt Dreben) that the only reason set theorists do not generally buy the view that V = L is that it would put them out of business by settling their open questions.
     From: William D. Hart (The Evolution of Logic [2010], 10)
     A reaction: Hart says V=L breaks with the interative conception of sets at level ω+1, which is countable is the constructible view, but has continuum many in the cumulative (iterative) hierarch. The constructible V=L view is anti-platonist.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naďve logical sets
Naďve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD]
     Full Idea: 'Comprehension' is the assumption that every predicate has an extension. Naďve set theory is the theory whose axioms are extensionality and comprehension, and comprehension is thought to be its naivety.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: This doesn't, of course, mean that there couldn't be a more modest version of comprehension. The notorious difficulty come with the discovery of self-referring predicates which can't possibly have extensions.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD]
     Full Idea: That the iterative sets suffice for most of ZFC does not show they are necessary, nor is it evident that the set of operations has no fixed points (as 0 is a fixed point for square-of), and no infinitely descending chains (like negative integers).
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: People don't seem to worry that they aren't 'necessary', and further measures are possible to block infinitely descending chains.
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD]
     Full Idea: We say that a binary relation R 'partially orders' a field A just in case R is irreflexive (so that nothing bears R to itself) and transitive. When the set is {a,b}, its subsets {a} and {b} are incomparable in a partial ordering.
     From: William D. Hart (The Evolution of Logic [2010], 1)
A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD]
     Full Idea: A partial ordering is a 'total ordering' just in case any two members of its field are comparable, that is, either a is R to b, or b is R to a, or a is b.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: See Idea 13457 for 'partial ordering'. The three conditions are known as the 'trichotomy' condition.
Von Neumann defines α<β as α∈β [Hart,WD]
     Full Idea: One of the glories of Von Neumann's theory of numbers is to define α < β to mean that α ∈ β.
     From: William D. Hart (The Evolution of Logic [2010], 3)
'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD]
     Full Idea: A total order 'well-orders' its field just in case any nonempty subset B of its field has an R-least member, that is, there is a b in B such that for any a in B different from b, b bears R to a. So less-than well-orders natural numbers, but not integers.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: The natural numbers have a starting point, but the integers are infinite in both directions. In plain English, an order is 'well-ordered' if there is a starting point.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Maybe sets should be rethought in terms of the even more basic categories [Hart,WD]
     Full Idea: Some have claimed that sets should be rethought in terms of still more basic things, categories.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: [He cites F.William Lawvere 1966] It appears to the the context of foundations for mathematics that he has in mind.
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Inferences are surely part of the causal structure of the world [Fodor]
     Full Idea: Inferences are surely part of the causal structure of the world.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §3)
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD]
     Full Idea: All the main set theories deny that there is a set of which everything is a member. No interpretation has a domain with everything in it. So the universal quantifier never gets to mean everything all at once; 'all' does not mean all.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: Could you have an 'uncompleted' universal set, in the spirit of uncompleted infinities? In ordinary English we can talk about 'absolutely everything' - we just can't define a set of everything. Must we 'define' our domain?
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Models are ways the world might be from a first-order point of view [Hart,WD]
     Full Idea: Models are ways the world might be from a first-order point of view.
     From: William D. Hart (The Evolution of Logic [2010], 9)
Model theory studies how set theory can model sets of sentences [Hart,WD]
     Full Idea: Modern model theory investigates which set theoretic structures are models for which collections of sentences.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: So first you must choose your set theory (see Idea 13497). Then you presumably look at how to formalise sentences, and then look at the really tricky ones, many of which will involve various degrees of infinity.
Model theory is mostly confined to first-order theories [Hart,WD]
     Full Idea: There is no developed methematics of models for second-order theories, so for the most part, model theory is about models for first-order theories.
     From: William D. Hart (The Evolution of Logic [2010], 9)
Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD]
     Full Idea: The beginning of modern model theory was when Morley proved Los's Conjecture in 1962 - that a complete theory in a countable language categorical in one uncountable cardinal is categorical in all.
     From: William D. Hart (The Evolution of Logic [2010], 9)
5. Theory of Logic / K. Features of Logics / 6. Compactness
First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD]
     Full Idea: First-order logic is 'compact', which means that any logical consequence of a set (finite or infinite) of first-order sentences is a logical consequence of a finite subset of those sentences.
     From: William D. Hart (The Evolution of Logic [2010], 3)
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / c. Berry's paradox
Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD]
     Full Idea: Berry's Paradox: by the least number principle 'the least number denoted by no description of fewer than 79 letters' exists, but we just referred to it using a description of 77 letters.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: I struggle with this. If I refer to 'an object to which no human being could possibly refer', have I just referred to something? Graham Priest likes this sort of idea.
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD]
     Full Idea: The Burali-Forti Paradox was a crisis for Cantor's theory of ordinal numbers.
     From: William D. Hart (The Evolution of Logic [2010], 3)
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD]
     Full Idea: In effect, the machinery introduced to solve the liar can always be rejigged to yield another version the liar.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: [He cites Hans Herzberger 1980-81] The machinery is Tarski's device of only talking about sentences of a language by using a 'metalanguage'.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD]
     Full Idea: We can show (using the axiom of choice) that the less-than relation, <, well-orders the ordinals, ...and that it partially orders the ordinals, ...and that it totally orders the ordinals.
     From: William D. Hart (The Evolution of Logic [2010], 1)
There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD]
     Full Idea: Since we can map the transfinite ordinals one-one into the infinite cardinals, there are at least as many infinite cardinals as transfinite ordinals.
     From: William D. Hart (The Evolution of Logic [2010], 1)
The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD]
     Full Idea: The axiom of infinity with separation yields a least limit ordinal, which is called ω.
     From: William D. Hart (The Evolution of Logic [2010], 3)
Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD]
     Full Idea: It is easier to generalize von Neumann's finite ordinals into the transfinite. All Zermelo's nonzero finite ordinals are singletons, but if ω were a singleton it is hard to see how if could fail to be the successor of its member and so not a limit.
     From: William D. Hart (The Evolution of Logic [2010], 3)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD]
     Full Idea: The real numbers were not isolated from geometry until the arithmetization of analysis during the nineteenth century.
     From: William D. Hart (The Evolution of Logic [2010], 1)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
We can establish truths about infinite numbers by means of induction [Hart,WD]
     Full Idea: Mathematical induction is a way to establish truths about the infinity of natural numbers by a finite proof.
     From: William D. Hart (The Evolution of Logic [2010], 5)
     A reaction: If there are truths about infinities, it is very tempting to infer that the infinities must therefore 'exist'. A nice, and large, question in philosophy is whether there can be truths without corresponding implications of existence.
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD]
     Full Idea: There is a familiar comparison between Euclid (unique parallel) and 'spherical' geometry (no parallel) and 'saddle' geometry (several parallels).
     From: William D. Hart (The Evolution of Logic [2010], 2)
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD]
     Full Idea: The thesis that no existence proposition is analytic is one of the few constants in philosophical consciences, but there are many existence claims in mathematics, such as the infinity of primes, five regular solids, and certain undecidable propositions.
     From: William D. Hart (The Evolution of Logic [2010], 2)
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD]
     Full Idea: Jespersen calls a noun a mass word when it has no plural, does not take numerical adjectives, and does not take 'fewer'.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: Jespersen was a great linguistics expert.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
We can take 'ways things might have been' as irreducible elements in our ontology [Stalnaker, by Lycan]
     Full Idea: Stalnaker suggests talking 'ways things might have been' as sui generis elements of our ontology - actual abstract entities in their own right, not to be reduced to more familiar items.
     From: report of Robert C. Stalnaker (Possible Worlds [1976]) by William Lycan - The Trouble with Possible Worlds 09
     A reaction: This seems to rest on an ontology of 'states of affairs', favoured by Armstrong, and implied in the Tractatus. How big is a state of affairs? How manys states of affairs can be co-present?
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD]
     Full Idea: The conception of Frege is that self-evidence is an intrinsic property of the basic truths, rules, and thoughts expressed by definitions.
     From: William D. Hart (The Evolution of Logic [2010], p.350)
     A reaction: The problem is always that what appears to be self-evident may turn out to be wrong. Presumably the effort of arriving at a definition ought to clarify and support the self-evident ingredient.
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD]
     Full Idea: In the case of the parallels postulate, Euclid's fifth axiom (the whole is greater than the part), and comprehension, saying was believing for a while, but what was said was false. This should make a shrewd philosopher sceptical about a priori knowledge.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Euclid's fifth is challenged by infinite numbers, and comprehension is challenged by Russell's paradox. I can't see a defender of the a priori being greatly worried about these cases. No one ever said we would be right - in doing arithmetic, for example.
13. Knowledge Criteria / C. External Justification / 5. Controlling Beliefs
Control of belief is possible if you know truth conditions and what causes beliefs [Fodor]
     Full Idea: Premeditated cognitive management is possible if knowing the contents of one's thoughts would tell you what would make them true and what would cause you to have them.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: I love the idea of 'cognitive management'. Since belief is fairly involuntary, I subject myself to the newspapers, books, TV and conversation which will create the style of beliefs to which I aspire. Why?
14. Science / A. Basis of Science / 3. Experiment
We can deliberately cause ourselves to have true thoughts - hence the value of experiments [Fodor]
     Full Idea: A creature that knows what makes its thoughts true and what would cause it to have them, could therefore cause itself to have true thoughts. …This would explain why experimentation is so close to the heart of our cognitive style.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
Interrogation and experiment submit us to having beliefs caused [Fodor]
     Full Idea: You can put yourself into a situation where you may be caused to believe that P. Putting a question to someone who is in the know is one species of this behaviour, and putting a question to Nature (an experiment) is another.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
Participation in an experiment requires agreement about what the outcome will mean [Fodor]
     Full Idea: To be in the audience for an experiment you have to believe what the experimenter believes about what the outcome would mean, but not necessarily what the outcome will be.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
An experiment is a deliberate version of what informal thinking does all the time [Fodor]
     Full Idea: Experimentation is an occasional and more or less self-conscious exercise in what informal thinking does all the time without thinking about it.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
14. Science / B. Scientific Theories / 1. Scientific Theory
Theories are links in the causal chain between the environment and our beliefs [Fodor]
     Full Idea: Theories function as links in the causal chains that run from environmental outcomes to the beliefs that they cause the inquirer to have.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
15. Nature of Minds / A. Nature of Mind / 1. Mind / e. Questions about mind
I say psychology is intentional, semantics is informational, and thinking is computation [Fodor]
     Full Idea: I hold that psychological laws are intentional, that semantics is purely informational, and that thinking is computation (and that it is possible to hold all of these assumptions at once).
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: When he puts it baldly like that, it doesn't sound terribly persuasive. Thinking is 'computation'? Raw experience is irrelevant? What is it 'like' to spot an interesting connection between two propositions or concepts? It's not like adding 7 and 5.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / f. Higher-order thought
We are probably the only creatures that can think about our own thoughts [Fodor]
     Full Idea: I think it is likely that we are the only creatures that can think about the contents of our thoughts.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: I think this is a major idea. If you ask me the traditional question - what is the essential difference between us and other animals? - this is my answer (not language, or reason). We are the metathinkers.
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
Semantics v syntax is the interaction problem all over again [Fodor]
     Full Idea: The question how mental representations could be both semantic, like propositions, and causal, like rocks, trees, and neural firings, is arguably just the interaction problem all over again.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: Interesting way of presenting the problem. If you seem to be confronting the interaction problem, you have probably drifted into a bogus dualist way of thinking. Retreat, and reformulate you questions and conceptual apparatus, till the question vanishes.
Cartesians consider interaction to be a miracle [Fodor]
     Full Idea: The Cartesian view is that the interaction problem does arise, but is unsolvable because interaction is miraculous.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: A rather unsympathetic statement of the position. Cartesians might think that God could explain to us how interaction works. Cartesians are not mysterians, I think, but they see no sign of any theory of interaction.
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
Type physicalism equates mental kinds with physical kinds [Fodor]
     Full Idea: Type physicalism is, roughly, the doctrine that psychological kinds are identical to neurological kinds.
     From: Jerry A. Fodor (The Elm and the Expert [1993], App A n.1)
     A reaction: This gets my general support, leaving open the nature of 'kinds'. Presumably the identity is strict, as in 'Hesperus is identical to Phosphorus'. It seems unlikely that if you and I think the 'same' thought, that we have strictly identical brain states.
17. Mind and Body / E. Mind as Physical / 4. Connectionism
Hume has no theory of the co-ordination of the mind [Fodor]
     Full Idea: What Hume didn't see was that the causal and representational properties of mental symbols have somehow to be coordinated if the coherence of mental life is to be accounted for.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: Certainly the idea that it all somehow becomes magic at the point where the brain represents the world is incoherent - but it is a bit magical. How can the whole of my garden be in my brain? Weird.
18. Thought / A. Modes of Thought / 2. Propositional Attitudes
Propositional attitudes are propositions presented in a certain way [Fodor]
     Full Idea: Propositional attitudes are really three-place relations, between a creature, a proposition, and a mode of presentation (which are sentences of Mentalese).
     From: Jerry A. Fodor (The Elm and the Expert [1993], §2.II)
     A reaction: I'm not sure about 'really'! Why do we need a creature? Isn't 'hoping it will rain' a propositional attitude which some creature may or may not have? Fodor wants it to be physical, but it's abstract?
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
Rationality has mental properties - autonomy, productivity, experiment [Fodor]
     Full Idea: Mentalism isn't gratuitous; you need it to explain rationality. Mental causation buys you behaviours that are unlike reflexes in at least three ways: they're autonomous, they're productive, and they're experimental.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: He makes his three ways sound all-or-nothing, which is (I believe) the single biggest danger when thinking about the mind. "Either you are conscious, or you are not..."
18. Thought / C. Content / 5. Twin Earth
XYZ (Twin Earth 'water') is an impossibility [Fodor]
     Full Idea: There isn't any XYZ, and there couldn't be any, and so we don't have to worry about it.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I)
     A reaction: Jadeite and Nephrite are real enough, which are virtually indistinguishable variants of jade. You just need Twin Jewellers instead of Twin Earths. We could build them, and employ twins to work there.
18. Thought / C. Content / 6. Broad Content
Truth conditions require a broad concept of content [Fodor]
     Full Idea: We need the idea of broad content to make sense of the fact that thoughts have the truth-conditions that they do.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §2.II)
     A reaction: There seems to be (as Dummett points out) a potential circularity here, as you can hardly know the truth-conditions of something if you don't already know its content.
18. Thought / C. Content / 7. Narrow Content
Concepts aren't linked to stuff; they are what is caused by stuff [Fodor]
     Full Idea: If the words of 'Swamp Man' (spontaneously created, with concepts) are about XYZ on Twin Earth, it is not because he's causally connected to the stuff, but because XYZ would cause his 'water' tokens (in the absence of H2O).
     From: Jerry A. Fodor (The Elm and the Expert [1993], App B)
     A reaction: The sight of the Eiffel tower causes my 'France' tokens, so is my word "France" about the Eiffel Tower? What would cause my 'nothing' tokens?
18. Thought / C. Content / 10. Causal Semantics
Knowing the cause of a thought is almost knowing its content [Fodor]
     Full Idea: If you know the content of a thought, you know quite a lot about what would cause you to have it.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: I'm not sure where this fits into the great jigsaw of the mind, but it strikes me as an acute and important observation. The truth of a thought is not essential to make you have it. Ask Othello.
18. Thought / C. Content / 12. Informational Semantics
Is content basically information, fixed externally? [Fodor]
     Full Idea: I assume intentional content reduces (in some way) to information. …The content of a thought depends on its external relations; on the way that the thought is related to the world, not the way that it is related to other thoughts.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2)
     A reaction: Does this make Fodor a 'weak' functionalist? The 'strong' version would say a thought is merely a location in a flow diagram, but Fodor's 'mentalism' includes a further 'content' in each diagram box.
18. Thought / D. Concepts / 3. Ontology of Concepts / b. Concepts as abilities
In the information view, concepts are potentials for making distinctions [Fodor]
     Full Idea: Semantics, according to the informational view, is mostly about counterfactuals; what counts for the identity of my concepts is not what I do distinguish but what I could distinguish if I cared to (even using instruments and experts).
     From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I)
     A reaction: We all differ in our discriminations (and awareness of expertise), so our concepts would differ, which is bad news for communication (see Idea 223). The view has some plausibility, though.
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD]
     Full Idea: A Fregean concept is a function that assigns to each object a truth value. So instead of the colour green, the concept GREEN assigns truth to each green thing, but falsity to anything else.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: This would seem to immediately hit the renate/cordate problem, if there was a world in which all and only the green things happened to be square. How could Frege then distinguish the green from the square? Compare Idea 8245.
19. Language / A. Nature of Meaning / 1. Meaning
Semantic externalism says the concept 'elm' needs no further beliefs or inferences [Fodor]
     Full Idea: It is the essence of semantic externalism that there is nothing that you have to believe, there are no inferences that you have to accept, to have the concept 'elm'.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §2.I)
     A reaction: [REMINDER: broad content is filed in 18.C.7, under 'Thought' rather than under language. That is because I am a philospher of thought, rather than of language.
If meaning is information, that establishes the causal link between the state of the world and our beliefs [Fodor]
     Full Idea: It is the causal connection between the state of the world and the contents of beliefs that the reduction of meaning to information is designed to insure.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: I'm not clear why characterising the contents of a belief in terms of its information has to amount to a 'reduction'. A cup of tea isn't reduced to tea. Connections imply duality.
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
To know the content of a thought is to know what would make it true [Fodor]
     Full Idea: If you know the content of a thought, you thereby know what would make the thought true.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: The truthmaker might by physically impossible, and careful thought might show it to be contradictory - but that wouldn't destroy the meaning.
19. Language / A. Nature of Meaning / 7. Meaning Holism / b. Language holism
For holists no two thoughts are ever quite the same, which destroys faith in meaning [Fodor]
     Full Idea: If what you are thinking depends on all of what you believe, then nobody ever thinks the same thing twice. …That is why so many semantic holists (Quine, Putnam, Rorty, Churchland, probably Wittgenstein) end up being semantic eliminativists.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2b)
     A reaction: If linguistic holism is nonsense, this is easily settled. What I say about breakfast is not changed by reading some Gibbon yesterday.
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
It is claimed that reference doesn't fix sense (Jocasta), and sense doesn't fix reference (Twin Earth) [Fodor]
     Full Idea: The standard view is that Frege cases [knowing Jocasta but not mother] show that reference doesn't determine sense, and Twin cases [knowing water but not H2O] show that sense doesn't determine reference.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §1.3)
     A reaction: How about 'references don't contain much information', and 'descriptions may not fix what they are referring to'? Simple really.
19. Language / C. Assigning Meanings / 2. Semantics
Broad semantics holds that the basic semantic properties are truth and denotation [Fodor]
     Full Idea: Broad semantic theories generally hold that the basic semantic properties of thoughts are truth and denotation.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §1.2b)
     A reaction: I think truth and denotation are the basic semantic properties, but I am dubious about whole-hearted broad semantic theories, so I seem to have gone horribly wrong somewhere.
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
Externalist semantics are necessary to connect the contents of beliefs with how the world is [Fodor]
     Full Idea: You need an externalist semantics to explain why the contents of beliefs should have anything to do with how the world is.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: Since externalist semantics only emerged in the 1970s, that implies that no previous theory had any notion that language had some connection to how the world is. Eh?