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All the ideas for 'fragments/reports', 'Philosophy of Logic' and 'Our Knowledge of the External World'

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48 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
A sense of timelessness is essential to wisdom [Russell]
     Full Idea: Both in thought and in feeling, to realize the unimportance of time is the gate of wisdom.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 6)
     A reaction: A very rationalist and un-Heraclitean view of wisdom. This picture may give wisdom a bad name, if wise people are (at a minimum) at least expected to give good advice about real life.
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophical disputes are mostly hopeless, because philosophers don't understand each other [Russell]
     Full Idea: Explicit controversy is almost always fruitless in philosophy, owing to the fact that no two philosophers ever understand one another.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 1)
     A reaction: Contemporaries don't even seem to read one another very much, especially these days, when there are thousands of professional philosophers. (If you are a professional, have you read all the works written by your colleagues and friends?)
1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Philosophical systems are interesting, but we now need a more objective scientific philosophy [Russell]
     Full Idea: The great systems of the past serve a very useful purpose, and are abundantly worthy of study. But something different is required if philosophy is to become a science, and to aim at results independent of the tastes of the philosophers who advocate them.
     From: Bertrand Russell (Our Knowledge of the External World [1914], Pref)
     A reaction: An interesting product of this move in philosophy is (about sixty years later) the work of David Lewis, who set out to be precise and scientific, and ended up creating a very personal system. Why not a collaborative system?
Hegel's confusions over 'is' show how vast systems can be built on simple errors [Russell]
     Full Idea: Hegel's confusion of the 'is' of predication with the 'is' of identity ...is an example of how, for want of care at the start, vast and imposing systems of philosophy are built upon stupid and trivial confusions.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 2 n1)
     A reaction: [He explains the confusion in more detail in the note] Russell cites an English translation, and I am wondering how this occurs in the German. Plato has been accused of similar elementary blunders about properties. Russell treats Berkeley similarly.
Philosophers sometimes neglect truth and distort facts to attain a nice system [Russell]
     Full Idea: The desire for unadulterated truth is often obscured, in professional philosophers, by love of system: the one little fact which will not come inside the philosophical edifice has to be pushed and tortured until it seems to consent.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 8)
     A reaction: Bit of hypocrisy here. Russell was continually trying to find a system, grounded in physics and logic. Presumably his shifting views are indications of integrity, because he changes the system rather than the facts.
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Physicists accept particles, points and instants, while pretending they don't do metaphysics [Russell]
     Full Idea: Physicists, ignorant and contemptuous of philosophy, have been content to assume their particles, points and instants in practice, while contending, with ironical politeness, that their concepts laid no claim to metaphysical validity.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 4)
     A reaction: Presumably physicists are allowed to wave their hands and utter the word 'instrumentalism', and then get on with the job. They just have to ensure they never speculate about what is being measured.
1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
When problems are analysed properly, they are either logical, or not philosophical at all [Russell]
     Full Idea: Every philosophical problem, when it is subjected to the necessary analysis and purification, is found either to be not really philosophical at all, or else to be, in the sense in which we are using the word, logical.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 2)
     A reaction: [All Lecture 2 discusses 'logical'] I think Bertie was getting carried away here. In his life's corpus he barely acknowledges the existence of ethics, or political philosophy, or aesthetics. He never even engages with 'objects' the way Aristotle does.
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.
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
Logic gives the method of research in philosophy [Russell]
     Full Idea: Logic gives the method of research in philosophy, just as mathematics gives the method in physics.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 8)
     A reaction: I'm struck by how rarely philosophers actually prove anything. Mostly they just use the language of logic as a tool for disambiguation. Only a tiny handful of philosophers can actually create sustained and novel proofs.
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 / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
The logical connectives are not objects, but are formal, and need a context [Russell]
     Full Idea: Such words as 'or' and 'not' are not names of definite objects, but are words that require a context in order to have a meaning. All of them are formal.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 7)
     A reaction: [He cites Wittgenstein's 1922 Tractatus in a footnote - presumably in a later edition than 1914] This is the most famous idea which Russell acquired from Wittgenstein. It was yet another step in his scaling down of ontology.
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.
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / a. Achilles paradox
The tortoise won't win, because infinite instants don't compose an infinitely long time [Russell]
     Full Idea: The idea that an infinite number of instants make up an infinitely long time is not true, and therefore the conclusion that Achilles will never overtake the tortoise does not follow.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 6)
     A reaction: Aristotle spotted this, but didn't express it as clearly as Russell.
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Atomic facts may be inferrable from others, but never from non-atomic facts [Russell]
     Full Idea: Perhaps one atomic fact may sometimes be capable of being inferred from another, though I do not believe this to be the case; but in any case it cannot be inferred from premises no one of which is an atomic fact.
     From: Bertrand Russell (Our Knowledge of the External World [1914], p.48)
     A reaction: I prefer Russell's caution to Wittgenstein's dogmatism. I presume utterly simple facts give you nothing to work with. Hegel thought that you could infer new concepts from given concepts.
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
A positive and negative fact have the same constituents; their difference is primitive [Russell]
     Full Idea: It must not be supposed that a negative fact contains a constituent corresponding to the word 'not'. It contains no more constituents than a positive fact of the correlative positive form. The differenece between the two forms is ultimate and irreducible.
     From: Bertrand Russell (Our Knowledge of the External World [1914], VIII.279), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 41 'Neg'
     A reaction: ['Harvard Lectures'] The audience disliked this. How does one fact exclude the other fact? Potter asks whether absence is a fact, and whether an absence can be a truthmaker.
8. Modes of Existence / A. Relations / 1. Nature of Relations
With asymmetrical relations (before/after) the reduction to properties is impossible [Russell]
     Full Idea: When we come to asymmetrical relations, such as before and after, greater and less etc., the attempt to reduce them to properties becomes obviously impossible.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 2)
     A reaction: The traditional Aristotelian reduction to properties is attributed by Russell to logic based on subject-predicate. As an example he cites being greater than as depending on more than the mere magnitudes of the entities. Direction of the relation.
8. Modes of Existence / B. Properties / 11. Properties as Sets
When we attribute a common quality to a group, we can forget the quality and just talk of the group [Russell]
     Full Idea: When a group of objects have the similarity we are inclined to attribute to possession of a common quality, the membership of the group will serve all the purposes of the supposed common quality ...which need not be assumed to exist.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 2)
     A reaction: This is the earliest account I have found of properties being treated as sets of objects. It more or less coincides with the invention of set theory. I am reminded of Idea 9208. What is the bazzing property? It's what those three things have in common.
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 / c. Representative realism
Science condemns sense-data and accepts matter, but a logical construction must link them [Russell]
     Full Idea: Men of science condemn immediate data as 'merely subjective', while maintaining the truths of physics from those data. ...The only justification possible for this must be one which exhibits matter as a logical construction from sense-data.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 4)
     A reaction: Since we blatantly aren't doing logic when we stare out of the window, this aspires to finding something like the 'logical form' of perception.
12. Knowledge Sources / B. Perception / 4. Sense Data / c. Unperceived sense-data
When sense-data change, there must be indistinguishable sense-data in the process [Russell]
     Full Idea: In all cases of sense-data capable of gradual change, we may find one sense-datum indistinguishable from another, and that indistinguishable from a third, while yet the first and third are quite easily distinguishable.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 5)
     A reaction: This point is key to the sense-data theory, because it gives them independent existence, standing between reality and subjective experience. It is also the reason why they look increasingly implausible, if they may not be experienced.
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Empirical truths are particular, so general truths need an a priori input of generality [Russell]
     Full Idea: All empirical evidence is of particular truths. Hence, if there is any knowledge of general truths at all, there must be some knowledge of general truths which is independent of empirical evidence.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 2)
     A reaction: Humean empiricists respond by being a sceptical of general truths. At this stage of his career Russell looks like a thoroughgoing rationalist, and he believes in the reality of universals, relations and propositions. He became more empirical later.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
Objects are treated as real when they connect with other experiences in a normal way [Russell]
     Full Idea: Objects of sense are called 'real' when they have the kind of connection with other objects of sense which experience has led us to regard as normal; when they fail this, they are called 'illusions'.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 3)
     A reaction: This rests rather too much on the concept of 'normal', but offers an attractive coherence account of perception. Direct perceptions are often invoked by anti-coherentists, but I think coherence is just as much needed in that realm.
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Global scepticism is irrefutable, but can't replace our other beliefs, and just makes us hesitate [Russell]
     Full Idea: Universal scepticism, though logically irrefutable, is practically barren; it can only, therefore, give a certain flavour of hesitancy to our beliefs, and cannot be used to substitute other beliefs for them.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 3)
     A reaction: Spot on. There is no positive evidence for scepticism, so must just register it as the faintest of possibilities, like the existence of secretive fairies.
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / c. Knowing other minds
Other minds seem to exist, because their testimony supports realism about the world [Russell, by Grayling]
     Full Idea: Russell gives an argument that other minds exist, because if one is entitled to believe this, then one can rely on the testimony of others, which, jointly with one's own experience, will give powerful support to the view that there a real spatial world.
     From: report of Bertrand Russell (Our Knowledge of the External World [1914], 3) by A.C. Grayling - Russell Ch.2
     A reaction: I rather like this argument. It is quite close to Wittgenstein's Private Language Argument, which also seems to refute scepticism about other minds. I think Russell's line, using testimony, knowledge and realism, may be better than Wittgenstein's.
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.
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
     Full Idea: Archelaus was the first person to say that the universe is boundless.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
We never experience times, but only succession of events [Russell]
     Full Idea: There is no reason in experience to suppose that there are times as opposed to events: the events, ordered by the relations of simultaneity and succession, are all that experience provides.
     From: Bertrand Russell (Our Knowledge of the External World [1914], 4)
     A reaction: We experience events, but also have quite an accurate sense of how much time has passed during the occurrence of events. If asked how much time has lapsed, why don't we say '32 events'? How do we distinguish long events from short ones?
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]
     Full Idea: Archelaus wrote that life on Earth began in a primeval slime.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus
     A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea.