Combining Texts

All the ideas for 'Consciousness', 'Sociobiology' and 'Philosophy of Logic'

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


50 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
If you say that a contradiction is true, you change the meaning of 'not', and so change the subject [Quine]
     Full Idea: Those who regard the conjunction p.not-p as true think they are talking about negation, 'not', but this ceases to be recognisable as negation. The deviant logician's predicament is when he tries to deny the doctrine he only changes the subject.
     From: Willard Quine (Philosophy of Logic [1970], Ch.6)
     A reaction: The charge of 'changing the subject' has become a classic move in modern discussions of non-standard logics. It is an important idea in discussions of arguments, and is found in Kant's account of the Ontological Argument.
3. Truth / F. Semantic Truth / 2. Semantic Truth
Talk of 'truth' when sentences are mentioned; it reminds us that reality is the point of sentences [Quine]
     Full Idea: The truth predicate has its utility in places where we are compelled to mention sentences. It then serves to point through the sentence to the reality; it serves as a reminder that though sentences are mentioned, reality is still the whole point.
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: A sensible interpretation of the Tarskian account of truth as disquotation. Quine neatly combines a common sense correspondence with a sophisticated logicians view of the role of truth. So what does "I want the truth here" mean?
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth is redundant for single sentences; we do better to simply speak the sentence [Quine]
     Full Idea: Rather than speak of truth, we do better simply to say the sentence and so speak not about language but about the world. Of singly given sentences, the perfect theory of truth is the 'disappearance theory of truth' (Sellars).
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: Quine defends truth as the crucial link between language and reality, but only for large groups of sentences. If someone accuses you of lying or being incorrect, you can respond by repeating your sentence in a firmer tone of voice.
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
We can eliminate 'or' from our basic theory, by paraphrasing 'p or q' as 'not(not-p and not-q)' [Quine]
     Full Idea: The construction of 'alternation' (using 'or') is useful in practice, but superfluous in theory. It can be paraphrased using only negation and conjunction. We say that 'p or q' is paraphrased as 'not(not-p and not-q)'.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: Quine treats 'not' and 'and' as the axiomatic logical connectives, and builds the others from those, presumably because that is the smallest number he could get it down to. I quite like it, because it seems to mesh with basic thought procedures.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Physicalism requires the naturalisation or rejection of set theory [Lycan]
     Full Idea: Eventually set theory will have to be either naturalised or rejected, if a thoroughgoing physicalism is to be maintained.
     From: William Lycan (Consciousness [1987], 8.4)
     A reaction: Personally I regard Platonism as a form of naturalism (though a rather bold and dramatic one). The central issue seems to be the ability of the human main/brain to form 'abstract' notions about the physical world in which it lives.
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
My logical grammar has sentences by predication, then negation, conjunction, and existential quantification [Quine]
     Full Idea: We chose a standard grammar in which the simple sentences are got by predication, and all further sentences are generated from these by negation, conjunction, and existential quantification.
     From: Willard Quine (Philosophy of Logic [1970], Ch.3)
     A reaction: It is interesting that we 'choose' our logic, apparently guided by an imperative to achieve minimal ontology. Of these basic ingredients, negation and predication are the more mysterious, especially the latter. Quine is a bit of an 'ostrich' about that.
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Maybe logical truth reflects reality, but in different ways in different languages [Quine]
     Full Idea: Perhaps the logical truths owe their truth to certain traits of reality which are reflected in one way by the grammar of our language, in another way by the grammar of another language, and in a third way by the grammar and lexicon of a third language.
     From: Willard Quine (Philosophy of Logic [1970], Ch.7)
     A reaction: This explains Quine's subsequent interest in translation, and the interest of his pupil Davidson in charity, and whether there could actually be rival conceptual schemes. I like the link between logical truths and reality, which follows Russell.
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Quine rejects second-order logic, saying that predicates refer to multiple objects [Quine, by Hodes]
     Full Idea: Quine is unwilling to suppose second-order logic intelligible. He holds to Mill's account of the referential role of a predicate: it multiply denotes any and all objects to which it applies, and there is no need for a further 'predicative' entity.
     From: report of Willard Quine (Philosophy of Logic [1970]) by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.130
     A reaction: If we assume that 'quantifying over' something is a commitment to its existence, then I think I am with Quine, because you end up with a massive commitment to universals, which I prefer to avoid.
Quantifying over predicates is treating them as names of entities [Quine]
     Full Idea: To put the predicate letter 'F' in a quantifier is to treat predicate position suddenly as name position, and hence to treat predicates as names of entities of some sort.
     From: Willard Quine (Philosophy of Logic [1970], Ch.5)
     A reaction: It is tricky to distinguish quantifying over predicates in a first-order way (by reifying them), and in a second-order way (where it is not clear whether you are quantifying over a property or a unified set of things.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle has three different definitions [Quine]
     Full Idea: The law of excluded middle, or 'tertium non datur', may be pictured variously as 1) Every closed sentence is true or false; or 2) Every closed sentence or its negation is true; or 3) Every closed sentence is true or not true.
     From: Willard Quine (Philosophy of Logic [1970], Ch.6)
     A reaction: Unlike many top philosophers, Quine thinks clearly about such things. 1) is the classical bivalent reading of excluded middle; 2) is the purely syntactic version; 3) leaves open how we interpret the 'not-true' option.
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Quantification theory can still be proved complete if we add identity [Quine]
     Full Idea: Complete proof procedures are available not only for quantification theory, but for quantification theory and identity together. Gödel showed that the theory is still complete if we add self-identity and the indiscernability of identicals.
     From: Willard Quine (Philosophy of Logic [1970], Ch.5)
     A reaction: Hence one talks of first-order logic 'with identity', even though, as Quine observes, it is unclear whether identity is actually a logical or a mathematical notion.
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
Names are not essential, because naming can be turned into predication [Quine]
     Full Idea: Names are convenient but redundant, because Fa is equivalent to (an x)(a=x,Fx), so a need only occur in the context a=, but this can be rendered as a simple predicate A, so that Fa gives way to (an x)(Ax.Fx).
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: In eliminating names from analysis, Quine takes Russell's strategy a step further. It is probably this which provoked Kripke into going right back to Mill's view of names as basic labels. The name/description boundary is blurred. Mr Gradgrind.
5. Theory of Logic / G. Quantification / 1. Quantification
Universal quantification is widespread, but it is definable in terms of existential quantification [Quine]
     Full Idea: Universal quantification is prominent in logical practice but superfluous in theory, since (for all x)Fx obviously amounts to not(exists an x)not-Fx.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: The equivalence between these two works both ways, some you could take the universal quantifier as primitive instead, which would make general truths prior to particular ones. Is there something deep at stake here?
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
You can't base quantification on substituting names for variables, if the irrationals cannot all be named [Quine]
     Full Idea: A customary argument against quantification based on substitution of names for variables refers to the theorem of set theory that irrational numbers cannot all be assigned integers. Although the integers can all be named, the irrationals therefore can't.
     From: Willard Quine (Philosophy of Logic [1970], Ch.6)
     A reaction: [He names Ruth Marcus as a source of substitutional quantification] This sounds like more than a mere 'argument' against substitutional quantification, but an actual disproof. Or maybe you just can't quantify once you run out of names.
Some quantifications could be false substitutionally and true objectually, because of nameless objects [Quine]
     Full Idea: An existential quantification could turn out false when substitutionally construed and true when objectually construed, because of there being objects of the purported kind but only nameless ones.
     From: Willard Quine (Philosophy of Logic [1970], Ch.6)
     A reaction: (Cf. Idea 9025) Some irrational numbers were his candidates for nameless objects, but as decimals they are infinite in length which seems unfair. I don't take even pi or root-2 to be objects in nature, so not naming irrationals doesn't bother me.
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Putting a predicate letter in a quantifier is to make it the name of an entity [Quine]
     Full Idea: To put the predicate letter 'F' in a quantifier is to treat predicate positions suddenly as name positions, and hence to treat predicates as names of entities of some sort.
     From: Willard Quine (Philosophy of Logic [1970], Ch.5)
     A reaction: Quine's famous objection to second-order logic. But Quine then struggles to give an account of predicates and properties, and hence is accused by Armstrong of being an 'ostrich'. Boolos 1975 also attacks Quine here.
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A sentence is logically true if all sentences with that grammatical structure are true [Quine]
     Full Idea: A sentence is logically true if all sentences with that grammatical structure are true.
     From: Willard Quine (Philosophy of Logic [1970], Ch.7)
     A reaction: Quine spends some time on the tricky question of deciding which parts of a sentence are grammatical structure ('syncategorematic'), and which parts are what he calls 'lexicon'. I bet there is a Quinean argument which blurs the boundary.
7. Existence / C. Structure of Existence / 2. Reduction
Types cannot be reduced, but levels of reduction are varied groupings of the same tokens [Lycan]
     Full Idea: If types cannot be reduced to more physical levels, this is not an embarrassment, as long as our institutional categories, our physiological categories, and our physical categories are just alternative groupings of the same tokens.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: This is a self-evident truth about a car engine, so I don't see why it wouldn't apply equally to a brain. Lycan's identification of the type as the thing which cannot be reduced seems a promising explanation of much confusion among philosophers.
Institutions are not reducible as types, but they are as tokens [Lycan]
     Full Idea: Institutional types are irreducible, though I assume that institutional tokens are reducible in the sense of strict identity, all the way down to the subatomic level.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: This seems a promising distinction, as the boundaries of 'institutions' disappear when you begin to reduce them to lower levels (cf. Idea 4601), and yet plenty of institutions are self-evidently no more than physics. Plants are invisible as physics.
7. Existence / C. Structure of Existence / 3. Levels of Reality
One location may contain molecules, a metal strip, a key, an opener of doors, and a human tragedy [Lycan]
     Full Idea: One space-time slice may be occupied by a collection of molecules, a metal strip, a key, an allower of entry to hotel rooms, a facilitator of adultery, and a destroyer souls.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: Desdemona's handkerchief is a nice example. This sort of remark seems to be felt by some philosophers to be heartless wickedness, and yet it so screamingly self-evident that it is impossible to deny.
7. Existence / E. Categories / 3. Proposed Categories
I see the 'role'/'occupant' distinction as fundamental to metaphysics [Lycan]
     Full Idea: I see the 'role'/'occupant' distinction as fundamental to metaphysics.
     From: William Lycan (Consciousness [1987], 4.0)
     A reaction: A passing remark in a discussion of functionalism about the mind, but I find it appealing. Causation is basic to materialistic metaphysics, and it creates networks of regular causes. It leaves open the essentialist question of WHY it has that role.
8. Modes of Existence / B. Properties / 12. Denial of Properties
Predicates are not names; predicates are the other parties to predication [Quine]
     Full Idea: Predicates are not names; predicates are the other parties to predication.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: Does a wife only exist as party to a marriage? There's something missing here. We are taking predication to be primitive, but we then seem to single out one part of the process - the object - while ignoring the remainder. What are Quinean objects?
9. Objects / A. Existence of Objects / 1. Physical Objects
A physical object is the four-dimensional material content of a portion of space-time [Quine]
     Full Idea: We might think of a physical object as simply the whole four-dimensional material content, however sporadic and heterogeneous, of some portion of space-time. If it is firm and coherent internally, we call it a body.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: An early articulation of one of the two standard views of objects in recent philosophy. I think I prefer the Quinean view, but I am still looking into that one...
9. Objects / E. Objects over Time / 4. Four-Dimensionalism
Four-d objects helps predication of what no longer exists, and quantification over items from different times [Quine]
     Full Idea: The four-dimensional view of objects aids relativity, and the grammar of tenses, but in logic it makes sense of applying a predicate to something that no longer exists, or of quantifying over objects that never coexisted at any one time.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: Since you can predicate of or quantify over hypothetical or fictional objects ('Hamlet is gloomy', 'phlogiston explained fire quite well', 'peace and quiet would be nice') I don't see the necessity for this bold ontological commitment, on these grounds.
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
Some conditionals can be explained just by negation and conjunction: not(p and not-q) [Quine]
     Full Idea: Often the purpose of a conditional, 'if p, q', can be served simply by negation and conjunction: not(p and not-q), the so-called 'material conditional'.
     From: Willard Quine (Philosophy of Logic [1970], Ch.2)
     A reaction: Logicians love the neatness of that, but get into trouble elsewhere with conditionals, particularly over the implications of not-p.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
I think greenness is a complex microphysical property of green objects [Lycan]
     Full Idea: Personally I favour direct realism regarding secondary qualities, and identify greenness with some complex microphysical property exemplified by green physical objects.
     From: William Lycan (Consciousness [1987], 8.4)
     A reaction: He cites D.M.Armstrong (1981) as his source. Personally I find this a bewildering proposal. Does he think there is greenness in grass AS WELL AS the emission of that wavelength of electro-magnetic radiation? Is greenness zooming through the air?
15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality
Intentionality comes in degrees [Lycan]
     Full Idea: Intentionality comes in degrees.
     From: William Lycan (Consciousness [1987], 5.4)
     A reaction: I agree. A footprint is 'about' a foot, in the sense of containing concentrated information about it. Can we, though, envisage a higher degree than human thought? Is there a maximum degree? Everything is 'about' everything, in some respect.
15. Nature of Minds / B. Features of Minds / 4. Intentionality / b. Intentionality theories
Teleological views allow for false intentional content, unlike causal and nomological theories [Lycan]
     Full Idea: The teleological view begins to explain intentionality, and in particular allows brain states and events to have false intentional content; causal and nomological theories of intentionality tend to falter on this last task.
     From: William Lycan (Consciousness [1987], 4.4)
     A reaction: Certainly if you say thought is 'caused' by the world, false thought become puzzling. I'm not sure I understand the rest of this, but it is an intriguing remark about a significant issue…
15. Nature of Minds / B. Features of Minds / 5. Qualia / c. Explaining qualia
Pain is composed of urges, desires, impulses etc, at different levels of abstraction [Lycan]
     Full Idea: Our phenomenal experience of pain has components - it is a complex, consisting (perhaps) of urges, desires, impulses, and beliefs, probably occurring at quite different levels of institutional abstraction.
     From: William Lycan (Consciousness [1987], 5.5)
     A reaction: This seems to be true, and offers the reductionist a strategy for making inroads into the supposed irreducable and fundamental nature of qualia. What's it like to be a complex hierarchically structured multi-functional organism?
The right 'level' for qualia is uncertain, though top (behaviourism) and bottom (particles) are false [Lycan]
     Full Idea: It is just arbitrary to choose a level of nature a priori as the locus of qualia, even though we can agree that high levels (such as behaviourism) and low-levels (such as the subatomic) can be ruled out as totally improbable.
     From: William Lycan (Consciousness [1987], 5.6)
     A reaction: Very good. People scream 'qualia!' whenever the behaviour level or the atomic level are proposed as the locations of the mind, but the suggestion that they are complex, and are spread across many functional levels in the middle sounds good.
17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique
If energy in the brain disappears into thin air, this breaches physical conservation laws [Lycan]
     Full Idea: By interacting causally, Cartesian dualism seems to violate the conservation laws of physics (concerning matter and energy). This seems testable, and afferent and efferent pathways disappearing into thin air would suggest energy is not conserved.
     From: William Lycan (Consciousness [1987], 1.1)
     A reaction: It would seem to be no problem as long as outputs were identical in energy to inputs. If the experiment could actually be done, the result might astonish us.
In lower animals, psychology is continuous with chemistry, and humans are continuous with animals [Lycan]
     Full Idea: Evolution has proceeded in all other known species by increasingly complex configurations of molecules and organs, which support primitive psychologies; our human psychologies are more advanced, but undeniably continuous with lower animals.
     From: William Lycan (Consciousness [1987], 1.1)
     A reaction: Personally I find the evolution objection to dualism highly persuasive. I don't see how anyone can take evolution seriously and be a dualist. If there is a dramatic ontological break at some point, a plausible reason would be needed for that.
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
Two behaviourists meet. The first says,"You're fine; how am I?" [Lycan]
     Full Idea: Old joke: two Behaviourists meet in the street, and the first says,"You're fine; how am I?"
     From: William Lycan (Consciousness [1987], n1.6)
     A reaction: This invites the response that introspection is uniquely authoritative about 'how we are', but this has been challenged quite a lot recently, which pushes us to consider whether these stupid behaviourists might actually have a good point.
17. Mind and Body / C. Functionalism / 1. Functionalism
Functionalism must not be too abstract to allow inverted spectrum, or so structural that it becomes chauvinistic [Lycan]
     Full Idea: The functionalist must find a level of characterisation of mental states that is not so abstract or behaviouristic as to rule out the possibility of inverted spectrum etc., nor so specific and structural as to fall into chauvinism.
     From: William Lycan (Consciousness [1987], 5.4)
     A reaction: If too specific then animals and aliens won't be able to implement the necessary functions; if the theory becomes very behaviouristic, then it loses interest in the possibility of an inverted spectrum. He is certainly right to hunt for a middle ground.
If functionalism focuses on folk psychology, it ignores lower levels of function [Lycan]
     Full Idea: 'Analytical functionalists', who hold that meanings of mental terms are determined by the causal roles associated with them by 'folk psychology', deny themselves appeals to lower levels of functional organisation.
     From: William Lycan (Consciousness [1987], 5.4)
     A reaction: Presumably folk psychology can fit into the kind of empirical methodology favoured by behaviourists, whereas 'lower levels' are going to become rather speculative and unscientific.
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
The distinction between software and hardware is not clear in computing [Lycan]
     Full Idea: Even the software/hardware distinction as it is literally applied within computer science is philosophically unclear.
     From: William Lycan (Consciousness [1987], 4.4)
     A reaction: This is true, and very important for functionalist theories of the mind. Even very volatile software is realised in 'hard' physics, and rewritable discs etc blur the distinction between 'programmable' and 'hardwired'.
17. Mind and Body / C. Functionalism / 5. Teleological Functionalism
Teleological characterisations shade off smoothly into brutely physical ones [Lycan]
     Full Idea: Highly teleological characterisations, unlike naďve and explicated mental characterisations, have the virtue of shading off fairly smoothly into (more) brutely physical ones.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: Thus the purpose of a car engine, and a spark plug, and the spark, and the temperature, and the vibration of molecules show a fading away of the overt purpose, disappearing into the pointless activity of electrons and quantum levels.
Mental types are a subclass of teleological types at a high level of functional abstraction [Lycan]
     Full Idea: I am taking mental types to form a small subclass of teleological types occurring for the most part at a high level of functional abstraction.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: He goes on to say that he understand teleology in evolutionary terms. There is always a gap between how you characterise or individuate something, and what it actually is. To say spanners are 'a small subclass of tools' is not enough.
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
Identity theory is functionalism, but located at the lowest level of abstraction [Lycan]
     Full Idea: 'Neuron' may be understood as a physiological term or a functional term, so even the Identity Theorist is a Functionalist - one who locates mental entities at a very low level of abstraction.
     From: William Lycan (Consciousness [1987], 5.4)
     A reaction: This is a striking observation, and somewhat inclines me to switch from identity theory to functionalism. If you ask what is the correct level of abstraction, Lycan's teleological-homuncular version refers you to all the levels.
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
Teleological functionalism helps us to understand psycho-biological laws [Lycan]
     Full Idea: Teleological functionalism helps us to understand the nature of biological and psychological laws, particularly in the face of Davidsonian scepticism about the latter.
     From: William Lycan (Consciousness [1987], 4.4)
     A reaction: Personally I doubt the existence of psycho-physical laws, but only because of the vast complexity. They would be like the laws of weather. 'Psycho-physical' laws seem to presuppose some sort of dualism.
We reduce the mind through homuncular groups, described abstractly by purpose [Lycan]
     Full Idea: I am explicating the mental in a reductive way, by reducing mental characterizations to homuncular institutional ones, which are teleological characterizations at various levels of functional abstraction.
     From: William Lycan (Consciousness [1987], 4.3)
     A reaction: I think this is the germ of a very good physicalist account of the mind. More is needed than a mere assertion about what the mind reduces to at the very lowest level; this offers a decent account of the descending stages of reduction.
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability
A Martian may exhibit human-like behaviour while having very different sensations [Lycan]
     Full Idea: Quite possibly a Martian's humanoid behaviour is prompted by his having sensations somewhat unlike ours, despite his superficial behavioural similarities to us.
     From: William Lycan (Consciousness [1987], 5.4)
     A reaction: I think this firmly refutes the multiple realisability objection to type-type physicalism. Mental events are individuated by their phenomenal features (known only to the user), and by their causal role (publicly available). These are separate.
19. Language / A. Nature of Meaning / 8. Synonymy
Single words are strongly synonymous if their interchange preserves truth [Quine]
     Full Idea: We can define, it would seem, a strong synonymy relation for single words by them being interchangeable salva veritate.
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: This is a first step in Quine's rejection of synonymous sentences. He goes on to raise the problem of renate/cordate. Presumably any two word types can have different connotations, and hence not always be interchangeable - in poetry, for example.
19. Language / D. Propositions / 6. Propositions Critique
It makes no sense to say that two sentences express the same proposition [Quine]
     Full Idea: My objection to propositions is not parsimony, or disapproval of abstract entities, ..but that propositions induce a relation of synonymy or equivalence between sentences (expressing the same proposition), and this makes no objective sense.
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: Personally I think propositions are unavoidable when you try to connect language to activities of the brain, and also when you consider animal thought. And also when you introspect about your own language processes. Mr Quine, he wrong.
There is no rule for separating the information from other features of sentences [Quine]
     Full Idea: There is no evident rule for separating the information from the stylistic or other immaterial features of the sentences.
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: There is no rule for deciding precisely when night falls, so I don't believe in night. I take a proposition, prima facie, as an answer to the question 'What exactly do you mean by that remark?' How do you extract logical form from sentences?
We can abandon propositions, and just talk of sentences and equivalence [Quine]
     Full Idea: Why not just talk of sentences and equivalence and let the propositions go? Propositions have been projected as shadows of sentences, but at best they will give us nothing the sentences will not give.
     From: Willard Quine (Philosophy of Logic [1970], Ch.1)
     A reaction: I don't understand how you decide that two sentences are equivalent. 'There's someone in that wood'; 'yes, there's a person amongst those trees'. Identical truth-conditions. We can formulate a non-linguistic fact about those truth-conditions.
19. Language / F. Communication / 5. Pragmatics / a. Contextual meaning
A good way of explaining an expression is saying what conditions make its contexts true [Quine]
     Full Idea: A reasonable way of explaining an expression is by saying what conditions make its various contexts true.
     From: Willard Quine (Philosophy of Logic [1970], Ch.3)
     A reaction: I like the circumspect phrasing of this, which carefully avoids any entities such as 'meanings' or 'truth conditions'. Maybe the whole core of philosophy of language should shift from theories of meaning to just trying to 'explain' sentences.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / d. Biological ethics
Genetic behaviours that have enhanced human success include aggression, rape and xenophobia [Wilson,EO, by Okasha]
     Full Idea: Wilson claimed that many human behaviours, including aggression, rape, and xenophobia, had a genetic basis, and were adaptations favoured by natural selection because they enhanced the reproductive success of our ancestors.
     From: report of Edmund O. Wilson (Sociobiology [1975]) by Samir Okasha - Philosophy of Science: Very Short Intro (2nd ed) 7
     A reaction: This led to the Sociobiology Wars, when E.O. Wilson was attacked by Richard Lewontin and Stephen Jay Gould.
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / b. Limited purposes
We need a notion of teleology that comes in degrees [Lycan]
     Full Idea: We need a notion of teleology that comes in degrees.
     From: William Lycan (Consciousness [1987], 4.4)
     A reaction: Anyone who says that key concepts, such as those concerning the mind, should come 'in degrees' wins my instant support. A whole car engine requires a very teleological explanation, the spark in the sparkplug far less so.
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
'Physical' means either figuring in physics descriptions, or just located in space-time [Lycan]
     Full Idea: An object is specifically physical if it figures in explanations and descriptions of features of ordinary non-living matter, as in current physics; it is more generally physical if it is simply located in space-time.
     From: William Lycan (Consciousness [1987], 8.5)
     A reaction: This gives a useful distinction when trying to formulate a 'physicalist' account of the mind, where type-type physicalism says only the 'postulates of physics' can be used, whereas 'naturalism' about the mind uses the more general concept.