Combining Philosophers

All the ideas for Anaxarchus, E.J. Lemmon and Robert Kirk

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68 ideas

4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic

9535	'Contradictory' propositions always differ in truth-value [Lemmon]
	Full Idea: Two propositions are 'contradictory' if they are never both true and never both false either, which means that ¬(A↔B) is a tautology.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / a. Symbols of PL

9512	We write the 'negation' of P (not-P) as ¬ [Lemmon]
	Full Idea: We write 'not-P' as ¬P. This is called the 'negation' of P. The 'double negation' of P (not not-P) would be written as ¬¬P.
	From: E.J. Lemmon (Beginning Logic [1965], 1.2)
	A reaction: Lemmons use of -P is no longer in use for 'not'. A tilde sign (squiggle) is also used for 'not', but some interpreters give that a subtly different meaning (involving vagueness). The sign ¬ is sometimes called 'hook' or 'corner'.

9511	We write the conditional 'if P (antecedent) then Q (consequent)' as P→Q [Lemmon]
	Full Idea: We write 'if P then Q' as P→Q. This is called a 'conditional', with P as its 'antecedent', and Q as its 'consequent'.
	From: E.J. Lemmon (Beginning Logic [1965], 1.2)
	A reaction: P→Q can also be written as ¬P∨Q.

9510	That proposition that either P or Q is their 'disjunction', written P∨Q [Lemmon]
	Full Idea: If P and Q are any two propositions, the proposition that either P or Q is called the 'disjunction' of P and Q, and is written P∨Q.
	From: E.J. Lemmon (Beginning Logic [1965], 1.3)
	A reaction: This is inclusive-or (meaning 'P, or Q, or both'), and not exlusive-or (Boolean XOR), which means 'P, or Q, but not both'. The ∨ sign is sometimes called 'vel' (Latin).

9514	If A and B are 'interderivable' from one another we may write A -||- B [Lemmon]
	Full Idea: If we say that A and B are 'interderivable' from one another (that is, A |- B and B |- A), then we may write A -||- B.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9508	The sign |- may be read as 'therefore' [Lemmon]
	Full Idea: I introduce the sign |- to mean 'we may validly conclude'. To call it the 'assertion sign' is misleading. It may conveniently be read as 'therefore'.
	From: E.J. Lemmon (Beginning Logic [1965], 1.2)
	A reaction: [Actually no gap between the vertical and horizontal strokes of the sign] As well as meaning 'assertion', it may also mean 'it is a theorem that' (with no proof shown).

9509	That proposition that both P and Q is their 'conjunction', written P∧Q [Lemmon]
	Full Idea: If P and Q are any two propositions, the proposition that both P and Q is called the 'conjunction' of P and Q, and is written P∧Q.
	From: E.J. Lemmon (Beginning Logic [1965], 1.3)
	A reaction: [I use the more fashionable inverted-v '∧', rather than Lemmon's '&', which no longer seems to be used] P∧Q can also be defined as ¬(¬P∨¬Q)

9513	We write 'P if and only if Q' as P↔Q; it is also P iff Q, or (P→Q)∧(Q→P) [Lemmon]
	Full Idea: We write 'P if and only if Q' as P↔Q. It is called the 'biconditional', often abbreviate in writing as 'iff'. It also says that P is both sufficient and necessary for Q, and may be written out in full as (P→Q)∧(Q→P).
	From: E.J. Lemmon (Beginning Logic [1965], 1.4)
	A reaction: If this symbol is found in a sequence, the first move in a proof is to expand it to the full version.

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL

9532	'Subcontrary' propositions are never both false, so that A∨B is a tautology [Lemmon]
	Full Idea: If A and B are expressible in propositional calculus notation, they are 'subcontrary' if they are never both false, which may be tested by the truth-table for A∨B, which is a tautology if they are subcontrary.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9533	A 'implies' B if B is true whenever A is true (so that A→B is tautologous) [Lemmon]
	Full Idea: One proposition A 'implies' a proposition B if whenever A is true B is true (but not necessarily conversely), which is only the case if A→B is tautologous. Hence B 'is implied' by A.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9516	A 'well-formed formula' follows the rules for variables, ¬, →, ∧, ∨, and ↔ [Lemmon]
	Full Idea: A 'well-formed formula' of the propositional calculus is a sequence of symbols which follows the rules for variables, ¬, →, ∧, ∨, and ↔.
	From: E.J. Lemmon (Beginning Logic [1965], 2.1)

9518	A 'theorem' is the conclusion of a provable sequent with zero assumptions [Lemmon]
	Full Idea: A 'theorem' of logic is the conclusion of a provable sequent in which the number of assumptions is zero.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)
	A reaction: This is what Quine and others call a 'logical truth'.

9528	A wff is a 'tautology' if all assignments to variables result in the value T [Lemmon]
	Full Idea: If a well-formed formula of propositional calculus takes the value T for all possible assignments of truth-values to its variables, it is said to be a 'tautology'.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9530	A wff is 'contingent' if produces at least one T and at least one F [Lemmon]
	Full Idea: If a well-formed formula of propositional calculus takes at least one T and at least one F for all the assignments of truth-values to its variables, it is said to be 'contingent'.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9517	The 'scope' of a connective is the connective, the linked formulae, and the brackets [Lemmon]
	Full Idea: The 'scope' of a connective in a certain formula is the formulae linked by the connective, together with the connective itself and the (theoretically) encircling brackets
	From: E.J. Lemmon (Beginning Logic [1965], 2.1)

9529	A wff is 'inconsistent' if all assignments to variables result in the value F [Lemmon]
	Full Idea: If a well-formed formula of propositional calculus takes the value F for all possible assignments of truth-values to its variables, it is said to be 'inconsistent'.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9519	A 'substitution-instance' is a wff formed by consistent replacing variables with wffs [Lemmon]
	Full Idea: A 'substitution-instance' is a wff which results by replacing one or more variables throughout with the same wffs (the same wff replacing each variable).
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

9531	'Contrary' propositions are never both true, so that ¬(A∧B) is a tautology [Lemmon]
	Full Idea: If A and B are expressible in propositional calculus notation, they are 'contrary' if they are never both true, which may be tested by the truth-table for ¬(A∧B), which is a tautology if they are contrary.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

9534	Two propositions are 'equivalent' if they mirror one another's truth-value [Lemmon]
	Full Idea: Two propositions are 'equivalent' if whenever A is true B is true, and whenever B is true A is true, in which case A↔B is a tautology.
	From: E.J. Lemmon (Beginning Logic [1965], 2.3)

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL

9397	CP: Given a proof of B from A as assumption, we may derive A→B [Lemmon]
	Full Idea: Conditional Proof (CP): Given a proof of B from A as assumption, we may derive A→B as conclusion, on the remaining assumptions (if any).
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9393	A: we may assume any proposition at any stage [Lemmon]
	Full Idea: Assumptions (A): any proposition may be introduced at any stage of a proof.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9399	∧E: Given A∧B, we may derive either A or B separately [Lemmon]
	Full Idea: And-Elimination (∧E): Given A∧B, we may derive either A or B separately. The conclusions will depend on the assumptions of the premiss.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9401	∨E: Derive C from A∨B, if C can be derived both from A and from B [Lemmon]
	Full Idea: Or-Elimination (∨E): Given A∨B, we may derive C if it is proved from A as assumption and from B as assumption. This will also depend on prior assumptions.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9398	∧I: Given A and B, we may derive A∧B [Lemmon]
	Full Idea: And-Introduction (&I): Given A and B, we may derive A∧B as conclusion. This depends on their previous assumptions.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9402	RAA: If assuming A will prove B∧¬B, then derive ¬A [Lemmon]
	Full Idea: Reduction ad Absurdum (RAA): Given a proof of B∧¬B from A as assumption, we may derive ¬A as conclusion, depending on the remaining assumptions (if any).
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9395	MTT: Given ¬B and A→B, we derive ¬A [Lemmon]
	Full Idea: Modus Tollendo Tollens (MTT): Given ¬B and A→B, we derive ¬A as a conclusion. ¬A depends on any assumptions that have been made
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9396	DN: Given A, we may derive ¬¬A [Lemmon]
	Full Idea: Double Negation (DN): Given A, we may derive ¬¬A as a conclusion, and vice versa. The conclusion depends on the assumptions of the premiss.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9394	MPP: Given A and A→B, we may derive B [Lemmon]
	Full Idea: Modus Ponendo Ponens (MPP): Given A and A→B, we may derive B as a conclusion. B will rest on any assumptions that have been made.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

9400	∨I: Given either A or B separately, we may derive A∨B [Lemmon]
	Full Idea: Or-Introduction (∨I): Given either A or B separately, we may derive A∨B as conclusion. This depends on the assumption of the premisses.
	From: E.J. Lemmon (Beginning Logic [1965], 1.5)

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL

9522	'Modus ponendo tollens' (MPT) says P, ¬(P ∧ Q) |- ¬Q [Lemmon]
	Full Idea: 'Modus ponendo tollens' (MPT) says that if the negation of a conjunction holds and also one of its conjuncts, then the negation of the other conjunct holds. Thus P, ¬(P ∧ Q) |- ¬Q may be introduced as a theorem.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)
	A reaction: Unlike Modus Ponens and Modus Tollens, this is a derived rule.

9521	'Modus tollendo ponens' (MTP) says ¬P, P ∨ Q |- Q [Lemmon]
	Full Idea: 'Modus tollendo ponens' (MTP) says that if a disjunction holds and also the negation of one of its disjuncts, then the other disjunct holds. Thus ¬P, P ∨ Q |- Q may be introduced as a theorem.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)
	A reaction: Unlike Modus Ponens and Modus Tollens, this is a derived rule.

9525	We can change conditionals into negated conjunctions with P→Q -||- ¬(P ∧ ¬Q) [Lemmon]
	Full Idea: The proof that P→Q -||- ¬(P ∧ ¬Q) is useful for enabling us to change conditionals into negated conjunctions
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

9524	We can change conditionals into disjunctions with P→Q -||- ¬P ∨ Q [Lemmon]
	Full Idea: The proof that P→Q -||- ¬P ∨ Q is useful for enabling us to change conditionals into disjunctions.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

9523	De Morgan's Laws make negated conjunctions/disjunctions into non-negated disjunctions/conjunctions [Lemmon]
	Full Idea: The forms of De Morgan's Laws [P∨Q -||- ¬(¬P ∧ ¬Q); ¬(P∨Q) -||- ¬P ∧ ¬Q; ¬(P∧Q) -||- ¬P ∨ ¬Q); P∧Q -||- ¬(¬P∨¬Q)] transform negated conjunctions and disjunctions into non-negated disjunctions and conjunctions respectively.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

9527	The Distributive Laws can rearrange a pair of conjunctions or disjunctions [Lemmon]
	Full Idea: The Distributive Laws say that P ∧ (Q∨R) -||- (P∧Q) ∨ (P∧R), and that P ∨ (Q∨R) -||- (P∨Q) ∧ (P∨R)
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

9526	We can change conjunctions into negated conditionals with P→Q -||- ¬(P → ¬Q) [Lemmon]
	Full Idea: The proof that P∧Q -||- ¬(P → ¬Q) is useful for enabling us to change conjunctions into negated conditionals.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)

4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables

9537	Truth-tables are good for showing invalidity [Lemmon]
	Full Idea: The truth-table approach enables us to show the invalidity of argument-patterns, as well as their validity.
	From: E.J. Lemmon (Beginning Logic [1965], 2.4)

9538	A truth-table test is entirely mechanical, but this won't work for more complex logic [Lemmon]
	Full Idea: A truth-table test is entirely mechanical, ..and in propositional logic we can even generate proofs mechanically for tautological sequences, ..but this mechanical approach breaks down with predicate calculus, and proof-discovery is an imaginative process.
	From: E.J. Lemmon (Beginning Logic [1965], 2.5)

4. Formal Logic / B. Propositional Logic PL / 4. Soundness of PL

9536	If any of the nine rules of propositional logic are applied to tautologies, the result is a tautology [Lemmon]
	Full Idea: If any application of the nine derivation rules of propositional logic is made on tautologous sequents, we have demonstrated that the result is always a tautologous sequent. Thus the system is consistent.
	From: E.J. Lemmon (Beginning Logic [1965], 2.4)
	A reaction: The term 'sound' tends to be used now, rather than 'consistent'. See Lemmon for the proofs of each of the nine rules.

4. Formal Logic / B. Propositional Logic PL / 5. Completeness of PL

9539	Propositional logic is complete, since all of its tautologous sequents are derivable [Lemmon]
	Full Idea: A logical system is complete is all expressions of a specified kind are derivable in it. If we specify tautologous sequent-expressions, then propositional logic is complete, because we can show that all tautologous sequents are derivable.
	From: E.J. Lemmon (Beginning Logic [1965], 2.5)
	A reaction: [See Lemmon 2.5 for details of the proofs]

4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC

13909	Write '(∀x)(...)' to mean 'take any x: then...', and '(∃x)(...)' to mean 'there is an x such that....' [Lemmon]
	Full Idea: Just as '(∀x)(...)' is to mean 'take any x: then....', so we write '(∃x)(...)' to mean 'there is an x such that....'
	From: E.J. Lemmon (Beginning Logic [1965], 3.1)
	A reaction: [Actually Lemmon gives the universal quantifier symbol as '(x)', but the inverted A ('∀') seems to have replaced it these days]

13902	'Gm' says m has property G, and 'Pmn' says m has relation P to n [Lemmon]
	Full Idea: A predicate letter followed by one name expresses a property ('Gm'), and a predicate-letter followed by two names expresses a relation ('Pmn'). We could write 'Pmno' for a complex relation like betweenness.
	From: E.J. Lemmon (Beginning Logic [1965], 3.1)

13911	The 'symbols' are bracket, connective, term, variable, predicate letter, reverse-E [Lemmon]
	Full Idea: I define a 'symbol' (of the predicate calculus) as either a bracket or a logical connective or a term or an individual variable or a predicate-letter or reverse-E (∃).
	From: E.J. Lemmon (Beginning Logic [1965], 4.1)

4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / b. Terminology of PC

13910	Our notation uses 'predicate-letters' (for 'properties'), 'variables', 'proper names', 'connectives' and 'quantifiers' [Lemmon]
	Full Idea: Quantifier-notation might be thus: first, render into sentences about 'properties', and use 'predicate-letters' for them; second, introduce 'variables'; third, introduce propositional logic 'connectives' and 'quantifiers'. Plus letters for 'proper names'.
	From: E.J. Lemmon (Beginning Logic [1965], 3.1)

4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / c. Derivations rules of PC

13904	Universal Elimination (UE) lets us infer that an object has F, from all things having F [Lemmon]
	Full Idea: Our rule of universal quantifier elimination (UE) lets us infer that any particular object has F from the premiss that all things have F. It is a natural extension of &E (and-elimination), as universal propositions generally affirm a complex conjunction.
	From: E.J. Lemmon (Beginning Logic [1965], 3.2)

13901	Predicate logic uses propositional connectives and variables, plus new introduction and elimination rules [Lemmon]
	Full Idea: In predicate calculus we take over the propositional connectives and propositional variables - but we need additional rules for handling quantifiers: four rules, an introduction and elimination rule for the universal and existential quantifiers.
	From: E.J. Lemmon (Beginning Logic [1965])
	A reaction: This is Lemmon's natural deduction approach (invented by Gentzen), which is largely built on introduction and elimination rules.

13903	Universal elimination if you start with the universal, introduction if you want to end with it [Lemmon]
	Full Idea: The elimination rule for the universal quantifier concerns the use of a universal proposition as a premiss to establish some conclusion, whilst the introduction rule concerns what is required by way of a premiss for a universal proposition as conclusion.
	From: E.J. Lemmon (Beginning Logic [1965], 3.2)
	A reaction: So if you start with the universal, you need to eliminate it, and if you start without it you need to introduce it.

13906	With finite named objects, we can generalise with &-Intro, but otherwise we need ∀-Intro [Lemmon]
	Full Idea: If there are just three objects and each has F, then by an extension of &I we are sure everything has F. This is of no avail, however, if our universe is infinitely large or if not all objects have names. We need a new device, Universal Introduction, UI.
	From: E.J. Lemmon (Beginning Logic [1965], 3.2)

13908	UE all-to-one; UI one-to-all; EI arbitrary-to-one; EE proof-to-one [Lemmon]
	Full Idea: Univ Elim UE - if everything is F, then something is F; Univ Intro UI - if an arbitrary thing is F, everything is F; Exist Intro EI - if an arbitrary thing is F, something is F; Exist Elim EE - if a proof needed an object, there is one.
	From: E.J. Lemmon (Beginning Logic [1965], 3.3)
	A reaction: [My summary of Lemmon's four main rules for predicate calculus] This is the natural deduction approach, of trying to present the logic entirely in terms of introduction and elimination rules. See Bostock on that.

4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / d. Universal quantifier ∀

13905	If there is a finite domain and all objects have names, complex conjunctions can replace universal quantifiers [Lemmon]
	Full Idea: If all objects in a given universe had names which we knew and there were only finitely many of them, then we could always replace a universal proposition about that universe by a complex conjunction.
	From: E.J. Lemmon (Beginning Logic [1965], 3.2)

4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃

13900	'Some Frenchmen are generous' is rendered by (∃x)(Fx→Gx), and not with the conditional → [Lemmon]
	Full Idea: It is a common mistake to render 'some Frenchmen are generous' by (∃x)(Fx→Gx) rather than the correct (∃x)(Fx&Gx). 'All Frenchmen are generous' is properly rendered by a conditional, and true if there are no Frenchmen.
	From: E.J. Lemmon (Beginning Logic [1965], 3.1)
	A reaction: The existential quantifier implies the existence of an x, but the universal quantifier does not.

5. Theory of Logic / B. Logical Consequence / 8. Material Implication

9520	The paradoxes of material implication are P |- Q → P, and ¬P |- P → Q [Lemmon]
	Full Idea: The paradoxes of material implication are P |- Q → P, and ¬P |- P → Q. That is, since Napoleon was French, then if the moon is blue then Napoleon was French; and since Napoleon was not Chinese, then if Napoleon was Chinese, the moon is blue.
	From: E.J. Lemmon (Beginning Logic [1965], 2.2)
	A reaction: This is why the symbol → does not really mean the 'if...then' of ordinary English. Russell named it 'material implication' to show that it was a distinctively logical operator.

7. Existence / C. Structure of Existence / 2. Reduction

4986	A weaker kind of reductionism than direct translation is the use of 'bridge laws' [Kirk,R]
	Full Idea: If multiple realisability means that psychological terms cannot be translated into physics, one weaker kind of reductionism resorts to 'bridge laws' which link the theory to be reduced to the reducing theory.
	From: Robert Kirk (Mind and Body [2003], §3.8)
	A reaction: It seems to me that reduction is all-or-nothing, so there can't be a 'weaker' kind. If they are totally separate but linked by naturally necessary laws (e.g. low temperature and ice), they are supervenient, but not reducible to one another.

13. Knowledge Criteria / D. Scepticism / 1. Scepticism

3061	Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius]
	Full Idea: Anaxarchus said that he was not even sure that he knew nothing.
	From: report of Anaxarchus (fragments/reports [c.340 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.10.1

15. Nature of Minds / B. Features of Minds / 1. Consciousness / c. Parts of consciousness

5001	Maybe we should see intentionality and consciousness as a single problem, not two [Kirk,R]
	Full Idea: Many philosophers today have adopted the view that we can achieve an enormous simplification by reducing the two components of the mind-body problem - intentionality and consciousness - into one; ...consciousness is no more than representations.
	From: Robert Kirk (Mind and Body [2003], §8.4)
	A reaction: One would then see subjective experience and informational content as two consequences of a single mental activity. This strikes me as the correct route to go. We do, after all, learn BY experiencing. Hence concepts are tied in with qualia.

15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality

4993	If a bird captures a worm, we could say its behaviour is 'about' the worm [Kirk,R]
	Full Idea: When a bird pulls a worm from the ground, then swallows it piece by piece, there is a sense in which its behaviour can be said to be about the worm.
	From: Robert Kirk (Mind and Body [2003], §5.4)
	A reaction: This is preparing the ground for a possible behaviourist account of intentionality. Reply: you could say rain is about puddles, or you could say we have adopted Dennett's 'intentional stance' to birds, but it tells us nothing about their psychology.

15. Nature of Minds / B. Features of Minds / 4. Intentionality / b. Intentionality theories

5000	Behaviourism says intentionality is an external relation; language of thought says it's internal [Kirk,R]
	Full Idea: The conflict over whether intentionality is a matter of behavioural relations with the rest of the world, or of the internal states of the subject, is at its most dramatic in the contrast between behaviourism and the language of thought hypothesis.
	From: Robert Kirk (Mind and Body [2003], §7.10)
	A reaction: I just don't believe any behaviourist external account of intentionality, which ducks the question of how it all works. Personally I am more drawn to maps and models than to a language of thought. I plan my actions in an imagined space-time world.

17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique

4982	Dualism implies some brain events with no physical cause, and others with no physical effect [Kirk,R]
	Full Idea: If the mind causes brain events, then they are not caused by other brain events, and such causal gaps should be detectable by scientists; there should also be a gap of brain-events which cause no other brain events, because they are causing mind events.
	From: Robert Kirk (Mind and Body [2003], §2.5)
	A reaction: This is the double causation problem which Spinoza had spotted (Idea 4862). Expressed this way, it seems a screamingly large problem for dualism. We should be able to discover some VERY strange physical activity in the brain.

17. Mind and Body / B. Behaviourism / 1. Behaviourism

4991	Behaviourism seems a good theory for intentional states, but bad for phenomenal ones [Kirk,R]
	Full Idea: For many kinds of mental states, notably intentional ones such as beliefs and desires, behaviourism is appealing, ..but for sensations and experiences such as pain, it seems grossly implausible.
	From: Robert Kirk (Mind and Body [2003], §5.1)
	A reaction: The theory does indeed make a bit more sense for intentional states, but it still strikes me as nonsense that there is no more to my belief that 'Whales live in the Atlantic' than a disposition to say something. WHY do I say this something?

4994	Behaviourism offers a good alternative to simplistic unitary accounts of mental relationships [Kirk,R]
	Full Idea: There is a temptation to think that 'aboutness', and the 'contents' of thoughts, and the relation of 'reference', are single and unitary relationships, but behaviourism offers an alternative approach.
	From: Robert Kirk (Mind and Body [2003], §5.5)
	A reaction: Personally I wouldn't touch behaviourism with a barge-pole (as it ducks the question of WHY certain behaviour occurs), but a warning against simplistic accounts of intentional states is good. I am sure there cannot be a single neat theory of refererence.

17. Mind and Body / B. Behaviourism / 2. Potential Behaviour

4992	In 'holistic' behaviourism we say a mental state is a complex of many dispositions [Kirk,R]
	Full Idea: There is a non-reductive version of behaviourism ( which we can call 'global' or 'holistic') which says there is no more to having mental states than having a complex of certain kinds of behavioural dispositions.
	From: Robert Kirk (Mind and Body [2003], §5.2)
	A reaction: This is designed to meet a standard objection to behaviourism - that there is no straight correlation between what I think and how I behave. The present theory is obviously untestable, because a full 'complex' of human dispositions is never repeated.

17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique

4990	The inverted spectrum idea is often regarded as an objection to behaviourism [Kirk,R]
	Full Idea: The inverted spectrum idea is often regarded as an objection to behaviourism.
	From: Robert Kirk (Mind and Body [2003], §4.5)
	A reaction: Thus, my behaviour at traffic lights should be identical, even if I have a lifelong inversion of red and green. A good objection. Note that physicalists can believe in inverted qualia as well a dualists, as long as the brain states are also inverted.

17. Mind and Body / E. Mind as Physical / 3. Eliminativism

4984	All meaningful psychological statements can be translated into physics [Kirk,R]
	Full Idea: All psychological statements which are meaningful, that is to say, which are in principle verifiable, are translatable into propositions which do not involve psychological concepts, but only the concepts of physics.
	From: Robert Kirk (Mind and Body [2003], §3.8)
	A reaction: This shows how eliminativist behaviourism arises out of logical positivism (by only allowing what is verifiable). The simplest objection: we can't verify the mental states of others, because they are private, but they are still the best explanation.

17. Mind and Body / E. Mind as Physical / 4. Connectionism

4998	Instead of representation by sentences, it can be by a distribution of connectionist strengths [Kirk,R]
	Full Idea: In a connectionist system, information is represented not by sentences but by the total distribution of connection strengths.
	From: Robert Kirk (Mind and Body [2003], §7.6)
	A reaction: Neither sentences (of a language of thought) NOR connection strengths strike me as very plausible ways for a brain to represent things. It must be something to do with connections, but it must also be to do with neurons, or we get bizarre counterexamples.

17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability

4985	If mental states are multiply realisable, they could not be translated into physical terms [Kirk,R]
	Full Idea: If psychological states are multiply realisable it is hard to see how they could possibly be translated into physical terms.
	From: Robert Kirk (Mind and Body [2003], §3.8)
	A reaction: Reductive funtionalism would do it. A writing iimplement is physical and multiply realisable. Personally I prefer the strategy of saying mental states are NOT multiply realisable. If frog brains differ from ours, they probably don't feel pain like us.

18. Thought / D. Concepts / 2. Origin of Concepts / c. Nativist concepts

4997	It seems unlikely that most concepts are innate, if a theory must be understood to grasp them [Kirk,R]
	Full Idea: It is widely accepted that for many concepts, if not all, grasping the concept requires grasping some theory, ...which makes difficulties for the view that concepts are not learned: for 'radical concept nativism', as Fodor calls it.
	From: Robert Kirk (Mind and Body [2003], §7.3)
	A reaction: Not a problem for traditional rationalist theories, where the whole theory can be innate along with the concept, but a big objection to modern more cautious non-holistic views (such as Fodor's). Does a bird have a concept AND theory of a nest?

19. Language / A. Nature of Meaning / 5. Meaning as Verification

4999	For behaviourists language is just a special kind of behaviour [Kirk,R]
	Full Idea: Behaviourists regard the use of language as just a special kind of behaviour.
	From: Robert Kirk (Mind and Body [2003], §7.9)
	A reaction: This is not an intuitively obvious view of language. We behave, and then we talk about behaviour. Performative utterances (like promising) have an obvious behavioural aspect, as do violent threats, but not highly theoretical language (such as maths).

19. Language / B. Reference / 1. Reference theories

4995	Behaviourists doubt whether reference is a single type of relation [Kirk,R]
	Full Idea: To most behaviourists it seems misguided to expect there to be a single relation that connects referring expressions with their referents.
	From: Robert Kirk (Mind and Body [2003], §5.5)
	A reaction: You don't need to be a behaviourist to feel this doubt. Think about names of real people, names of fictional people, reference to misunderstood items, or imagined items, or reference in dreams, or to mathematical objects, or negations etc.