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All the ideas for 'reports', 'My Philosophical Development' and 'Truth and Truthmakers'

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71 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius]
     Full Idea: He studied philosophy on the principle of suspending his judgement on all points.
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.3
     A reaction: In what sense was Pyrrho a philosopher, then? He must have asserted SOME generalised judgments.
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
All metaphysical discussion should be guided by a quest for truthmakers [Armstrong]
     Full Idea: My plea, whatever conclusions are drawn, is to control the metaphysical discussion by continual reference to suggested truthmakers.
     From: David M. Armstrong (Truth and Truthmakers [2004], 08.7)
     A reaction: ...And my plea is to control metaethical discussion by continual reference to value-makers. In general, this is the approach which will deliver a unified account of the world. Truthmakers are the ideal restraint on extravagant metaphysics.
1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
Only by analysing is progress possible in philosophy [Russell]
     Full Idea: I remain firmly persuaded, in spite of some modern tendencies to the contrary, that only by analysing is progress possible, …for example, by analysing physics and perception, the problem of mind and matter can be completely solved.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.1)
     A reaction: I don't share his confidence in the second part of this, but I subscribe to the maxim that 'analsis is the path to wisdom'. It is a very western view, and lots of people (mostly of a mystical disposition) hate it, but I see no better path.
Analysis gives new knowledge, without destroying what we already have [Russell]
     Full Idea: It seems to me evident that, as in the case of impure water, analysis gives new knowledge without destroying any of the previously existing knowledge.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.11)
     A reaction: I agree. On the whole, opponents of analysis are sentimental mystics who are reluctant to think carefully about life. I'm not sure what careful and concentrated thought is capable of, apart from analysis.
2. Reason / A. Nature of Reason / 9. Limits of Reason
Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius]
     Full Idea: The Sceptics say that they only employ reason as an instrument, because it is impossible to overturn the authority of reason, without employing reason.
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.8
2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
The theory of types makes 'Socrates and killing are two' illegitimate [Russell]
     Full Idea: 'Socrates and killing are two' would be an illegitimate sentence according to the doctrine of types.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.14)
     A reaction: This nicely shows how Ryle's notion of a 'category mistake', although it is a commonsense observation of bogus reasoning, arises out of Russell's logical analysis of sets. Of course, the theory of types has its critics.
3. Truth / A. Truth Problems / 5. Truth Bearers
Truth belongs to beliefs, not to propositions and sentences [Russell]
     Full Idea: Truth and falsehood both belong primarily to beliefs, and only derivatively to propositions and sentences.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.15)
     A reaction: I'm not sure why a proposition which is date/place stamped ('it is raining, here and now') could not be considered a truth, even if no one believed it. Is not the proposition 'squares have four sides' true?
3. Truth / B. Truthmakers / 4. Truthmaker Necessitarianism
Truth-making can't be entailment, because truthmakers are portions of reality [Armstrong]
     Full Idea: Truth-making cannot be any form of entailment. Both terms of an entailment relation must be propositions, but the truth-making term of the truth-making relation is a portion of reality, and, in general at least, portions of reality are not propositions.
     From: David M. Armstrong (Truth and Truthmakers [2004], 02.3)
     A reaction: Along with Idea 18466, that seems to firmly demolish the idea that truth-making is a logical entailment.
Armstrong says truthmakers necessitate their truth, where 'necessitate' is a primitive relation [Armstrong, by MacBride]
     Full Idea: In a bold manouevre Armstrong posited a metaphysically primitive relation of necessitation, and then defined truth-makers in terms of this bridging relation, as a thing that necessitates something being true.
     From: report of David M. Armstrong (Truth and Truthmakers [2004], 02.3) by Fraser MacBride - Truthmakers 1.2
     A reaction: [Not sure of page reference] Spelled out so clearly by MacBride, this sounds dubious. How many truths are necessitated by the City of London? Do truthmakers necessitate the existence of their truths? MacBride says it's a circular theory.
3. Truth / B. Truthmakers / 6. Making Negative Truths
Negative truths have as truthmakers all states of affairs relevant to the truth [Armstrong]
     Full Idea: Postulate a higher-order state of affairs, of all the states of affairs in which Theaetetus is involved. Is this not a good candidate for a truthmaker for the negative truth that 'Theaetetus is not flying'?
     From: David M. Armstrong (Truth and Truthmakers [2004], 05.2)
     A reaction: It certainly seems extravagant to need the whole universe to make true 'there are no lions in this room'. But for 'there are no unicorns' it is not clear which states of affairs unicorns are involved. (Armstrong is aware of this).
The nature of arctic animals is truthmaker for the absence of penguins there [Armstrong]
     Full Idea: Each of the arctic animals is by its nature different from a penguin, so this general state of affairs seems truthmaker enough for this negative existential. Similarly, the totality of all birds eliminates the phoenix.
     From: David M. Armstrong (Truth and Truthmakers [2004], 06.2)
     A reaction: Why is it 'animals' in one case, and 'birds' in the other? What if there was no life in arctic? Would the snow then do the job? This doesn't seem to work.
3. Truth / B. Truthmakers / 7. Making Modal Truths
In mathematics, truthmakers are possible instantiations of structures [Armstrong]
     Full Idea: A mathematical entity exists if and only if it is possible that there be instantiations of that structure. This transforms the question of truthmakers for the existence of mathematical entities into a question of truthmakers for certain possibilities.
     From: David M. Armstrong (Truth and Truthmakers [2004], 09.3)
     A reaction: This modal approach to structuralism [for which he endorses Hellman 1989] opens up a modal approach to other truthmakers, which places dispositions at the centre of physical truthmaking. No sets of Meinongian objects?
One truthmaker will do for a contingent truth and for its contradictory [Armstrong]
     Full Idea: It seems reasonable to say that a truthmaker for a contingent truth is also a truthmaker for the truth that the contradictory of that truth is possible.
     From: David M. Armstrong (Truth and Truthmakers [2004], 07.2)
     A reaction: The truthmaker will have to be not only some fact, but also the additional fact that it is contingent, in order to generate the possibility of the contradictory.
The truthmakers for possible unicorns are the elements in their combination [Armstrong]
     Full Idea: The obvious minimal truthmaker for the truth that 'it is possible that a unicorn exists' is combinatorial. The elements of the combination are all that is needed.
     From: David M. Armstrong (Truth and Truthmakers [2004], 07.5)
     A reaction: This seems to imply that there are no possibilities which are not combinations of what currently exists.
What is the truthmaker for 'it is possible that there could have been nothing'? [Armstrong]
     Full Idea: It is possible that there could have been nothing. ...What would be its truthmaker?
     From: David M. Armstrong (Truth and Truthmakers [2004], 07.4)
     A reaction: I suppose the truthmaker here is the whole of reality, with its dispositions and contingencies. But that won't do for 'possibly there might never have been anything'. In such a case there wouldn't be any truths.
3. Truth / B. Truthmakers / 8. Making General Truths
Necessitating general truthmakers must also specify their limits [Armstrong]
     Full Idea: The mereological sum of what happens to be all the men does not necessitate that it is all the men. So if truthmaking involves necessitation, then this object cannot be the complete truthmaker for .
     From: David M. Armstrong (Truth and Truthmakers [2004], 06.1)
     A reaction: [He invokes Russell has his source] His point is that the truthmaker needs a further fact, beyond the men, which specifies that this is all of them. But only if truthmakers necessitate their truths (as Armstrong claims). I'm sympathetic to both claims.
4. Formal Logic / F. Set Theory ST / 1. Set Theory
The set theory brackets { } assert that the member is a unit [Armstrong]
     Full Idea: The idea is that braces { } attribute to an entity the place-holding, or perhaps determinable, property of unithood.
     From: David M. Armstrong (Truth and Truthmakers [2004], 09.5)
     A reaction: I like this. There is Socrates himself, then there is my concept , and then there is the singleton {Socrates}. Those braces must add something to the concept. You can't add braces to Socrates himself.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
For 'there is a class with no members' we don't need the null set as truthmaker [Armstrong]
     Full Idea: The null class is useful in formal set theory, but I hope that does not require that there be a thing called the null class which is truthmaker for the strange proposition .
     From: David M. Armstrong (Truth and Truthmakers [2004], 09.1)
     A reaction: It is not quite clear why it doesn't, but then it is not quite clear to philosophers what the status of the null set is, in comparison with sets that have members.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
I gradually replaced classes with properties, and they ended as a symbolic convenience [Russell]
     Full Idea: My original use of classes was gradually more and more replaced by properties, and in the end disappeared except as a symbolic convenience.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.14)
     A reaction: I wish I knew what properties are. On the whole, though, I agree with this, because it is more naturalistic. We may place things in classes because of their properties, and this means there are natural classes, but classes can't have a life of their own.
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Leibniz bases everything on subject/predicate and substance/property propositions [Russell]
     Full Idea: The metaphysics of Leibniz was explicitly based upon the doctrine that every proposition attributes a predicate to a subject and (what seemed to him almost the same thing) that every fact consists of a substance having a property.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.5)
     A reaction: I think it is realised now that although predicates tend to attribute properties to things, they are far from being the same thing. See Idea 4587, for example. Russell gives us an interesting foot in the door of Leibniz's complex system.
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
Names are meaningless unless there is an object which they designate [Russell]
     Full Idea: Unlike descriptions, names are meaningless unless there is an object which they designate.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.14)
     A reaction: This interests Russell because of its ontological implications. If we reduce language to names, we can have a pure ontology of 'objects'. We need a system for saying whether a description names something - which is his theory of definite descriptions.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / a. Units
Classes have cardinalities, so their members must all be treated as units [Armstrong]
     Full Idea: Classes, because they have a particular cardinality, are essentially a certain number of ones, things that, within the particular class, are each taken as a unit.
     From: David M. Armstrong (Truth and Truthmakers [2004], 09.1)
     A reaction: [Singletons are exceptions] So units are basic to set theory, which is the foundations of technical analytic philosophy (as well as, for many, of mathematics). If you can't treat something as a unit, it won't go into set theory. Vagueness...
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
We tried to define all of pure maths using logical premisses and concepts [Russell]
     Full Idea: The primary aim of our 'Principia Mathematica' was to show that all pure mathematics follows from purely logical premisses and uses only concepts definable in logical terms.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.7)
     A reaction: This spells out the main programme of logicism, by its great hero, Russell. The big question now is whether Gödel's Incompleteness Theorems have succeeded in disproving logicism.
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Formalists say maths is merely conventional marks on paper, like the arbitrary rules of chess [Russell]
     Full Idea: The Formalists, led by Hilbert, maintain that arithmetic symbols are merely marks on paper, devoid of meaning, and that arithmetic consists of certain arbitrary rules, like the rules of chess, by which these marks can be manipulated.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.10)
     A reaction: I just don't believe that maths is arbitrary, and this view pushes me into the arms of the empiricists, who say maths is far more likely to arise from experience than from arbitrary convention. The key to maths is patterns.
Formalism can't apply numbers to reality, so it is an evasion [Russell]
     Full Idea: Formalism is perfectly adequate for doing sums, but not for the application of number, such as the simple statement 'there are three men in this room', so it must be regarded as an unsatisfactory evasion.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.10)
     A reaction: This seems to me a powerful and simple objection. The foundation of arithmetic is that there are three men in the room, not that one plus two is three. Three men and three ties make a pattern, which we call 'three'.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionism says propositions are only true or false if there is a method of showing it [Russell]
     Full Idea: The nerve of the Intuitionist theory, led by Brouwer, is the denial of the law of excluded middle; it holds that a proposition can only be accounted true or false when there is some method of ascertaining which of these it is.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.2)
     A reaction: He cites 'there are three successive sevens in the expansion of pi' as a case in point. This seems to me an example of the verificationism and anti-realism which is typical of that period. It strikes me as nonsense, but Russell takes it seriously.
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
In 1899-1900 I adopted the philosophy of logical atomism [Russell]
     Full Idea: In the years 1899-1900 I adopted the philosophy of logical atomism.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.1)
     A reaction: This is interesting (about Russell) because he only labelled it as 'logical atomism' in about 1912, and only wrote about it as such in 1918. It is helpful to understand that the theory of definite descriptions was part of his logical atomism.
Complex things can be known, but not simple things [Russell]
     Full Idea: I have come to think that, although many things can be known to be complex, nothing can be known to be simple.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.14)
     A reaction: This appears to be a rejection of his logical atomism. It goes with a general rebellion against foundationalist epistemology, because the empiricists foundations (e.g. Hume's impressions) seem devoid of all content.
Logical atomism builds on the simple properties, but are they the only possible properties? [Armstrong]
     Full Idea: One of the assumptions of logical atomism is that all structural properties, all complex properties, are composed of simple properties and relations. ...But does the totality of the simple properties consist of the only possible simple properties?
     From: David M. Armstrong (Truth and Truthmakers [2004], 07.3)
     A reaction: This refers to what Lewis calls 'alien' properties - possible properties that cannot even be constructed from actual properties. Armstrong's question is about the truthmakers for such things. A bit speculative...
7. Existence / D. Theories of Reality / 5. Naturalism
'Naturalism' says only the world of space-time exists [Armstrong]
     Full Idea: I define 'naturalism' as the hypothesis that the world of space-time is all that there is.
     From: David M. Armstrong (Truth and Truthmakers [2004], 09.1)
     A reaction: This is helpful, because it doesn't mention the nature of the physical matter contained in space-time, leaving theories like panpsychism as possible naturalistic theories. Galen Strawson, for example.
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
Facts are everything, except simples; they are either relations or qualities [Russell]
     Full Idea: Facts, as I am using the word, consist always of relations between parts of a whole or qualities of single things; facts, in a word, are whatever there is except what (if anything) is completely simple.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.13)
     A reaction: This is the view that goes with Russell's 'logical atomism', where the 'completely simple' is used to build up the 'facts'. If World War One was a fact, was it a 'relation' or a 'quality'. Must events then be defined in terms of those two?
7. Existence / D. Theories of Reality / 9. States of Affairs
Truthmaking needs states of affairs, to unite particulars with tropes or universals. [Armstrong]
     Full Idea: There must exist states of affairs as truthmakers, to get us beyond 'loose and separate' entities. ...They can be bundles of tropes, or trope-with-particular, or bundles of universals ('compresence'), or instantiations. They are an addition to ontology.
     From: David M. Armstrong (Truth and Truthmakers [2004], 04.5)
     A reaction: Armstrong is the great champion of states of affairs. They seem rather vague to me, and disconcertingly timeless.
8. Modes of Existence / B. Properties / 2. Need for Properties
We need properties, as minimal truthmakers for the truths about objects [Armstrong]
     Full Idea: The 'thing itself' seems not be a minimal truthmaker for the thing having its particular mass. ...The thing has a great many other properties. ...It seems entirely reasonable to postulate that the object has properties that are objectively there.
     From: David M. Armstrong (Truth and Truthmakers [2004], 04.2)
     A reaction: This is Armstrong using the truthmaker principle to argue for the existence of properties (as instantiated universals). I like truthmakers, but truths do not have enough precision in their parts for us to read off reality from them.
8. Modes of Existence / B. Properties / 3. Types of Properties
The determinates of a determinable must be incompatible with each other [Armstrong]
     Full Idea: A set of determinates under the one determinable are incompatible by definition. If an object is not one mile in length, then its actual length will be incompatible with being one mile in length.
     From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.1)
     A reaction: This is a much better general version of the standard example 'if it is red it can't be green'. Armstrong uses it to give a more precise account of incompatibility. Useful.
Length is a 'determinable' property, and one mile is one its 'determinates' [Armstrong]
     Full Idea: Length is a 'determinable' property; being some particular length, such as a mile, is one of its 'determinates'.
     From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.1)
     A reaction: The seem to be 'type' and 'token' properties, except that this other vocabulary indicates the link between them.
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
If tropes are non-transferable, then they necessarily belong to their particular substance [Armstrong]
     Full Idea: 'Non-transferable' theories of tropes hold that the mass is of this stone by necessity. It is an identity condition for the property. Every property then becomes an essential property.
     From: David M. Armstrong (Truth and Truthmakers [2004], 04.3)
     A reaction: [He cites Martin and Heil for this view] It is hard to see in this proposal how the trope is in any way separate from its substance, and hence it seems a bit of a vacuous theory. (The other theories of properties aren't much cop either).
8. Modes of Existence / C. Powers and Dispositions / 5. Powers and Properties
Properties are not powers - they just have powers [Armstrong]
     Full Idea: Properties are not powers. But properties have powers. They bestow powers.
     From: David M. Armstrong (Truth and Truthmakers [2004], 10.4)
     A reaction: I think this is the wrong way round. In this view, powers become extremely vague things, ranging from the fine-grained to the hugely broad. It seems to me that powers are precise and real, but properties are the vague unhelpful things.
8. Modes of Existence / C. Powers and Dispositions / 7. Against Powers
Powers must result in some non-powers, or there would only be potential without result [Armstrong]
     Full Idea: Powers must surely issue in manifestations that are something more than just powers. A world where potency never issued in act, but only in more potency, would be one where one travelled without ever having the possibility of arriving.
     From: David M. Armstrong (Truth and Truthmakers [2004], 10.4)
     A reaction: Tricky. The picture I favour is that the distinction between powers and categorical properties is a misunderstanding. What is fundamental is active and powerful categoricals.
How does the power of gravity know the distance it acts over? [Armstrong]
     Full Idea: If masses are powers, the forces generated between two particulars have to vary inversely with the square of their distance apart. Have not the masses got to 'know' at what distance they are from each other, to exert the right amount of force?
     From: David M. Armstrong (Truth and Truthmakers [2004], 10.4)
     A reaction: This seems like a good warning against a simplistic account of powers doing all the work, but I suspect that more sophisticated physics would offer the fan of powers a solution here. The power is to 'spread' the force around.
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
Universals can't just be words, because words themselves are universals [Russell]
     Full Idea: Those who dislike universals have thought that they could be merely words; the trouble with this view is that a word itself is a universal.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.14)
     A reaction: Russell gradually lost his faith in most things, but never in universals. I find it unconvincing that we might dismiss nominalism so easily. I'm not sure why the application of the word 'cat' could not just be conventional.
8. Modes of Existence / E. Nominalism / 5. Class Nominalism
The class of similar things is much too big a truthmaker for the feature of a particular [Armstrong]
     Full Idea: For a Class Nominalist 'the class of all 4-kilo objects' is the truthmaker for the truth that the particular has just that mass. Yet this looks far too big! Would not the object still be four kilos even if the other members of the class had never existed?
     From: David M. Armstrong (Truth and Truthmakers [2004], 04.2)
     A reaction: This seems so obvious to me as to be hardly worth saying. To identify redness with the class of red entities just seems crazy. Why do they belong in that class? Armstrong is illustrating the value of the truthmaker idea in philosophy.
9. Objects / F. Identity among Objects / 1. Concept of Identity
When entities contain entities, or overlap with them, there is 'partial' identity [Armstrong]
     Full Idea: There is 'partial identity' where one entity contains another with something to spare, or else where entities overlap each other. ...Extensive quantities, such as length and mass, are the particularly plausible cases.
     From: David M. Armstrong (Truth and Truthmakers [2004], 08.5)
     A reaction: This looks like a very useful concept which deserves wider use. It will help discussions of rivers, statues, intersecting roads etc.
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Possible worlds don't fix necessities; intrinsic necessities imply the extension in worlds [Armstrong]
     Full Idea: It seems natural and plausible to say that it is the fact that a necessary truth is itself necessary that determines its truth in all possible worlds. This intension determines its extension across possible worlds.
     From: David M. Armstrong (Truth and Truthmakers [2004], 08.1)
     A reaction: Well said. To me (but not to Armstrong) this implies essentialism, that the necessity arises from the intrinsic natures of the things involved. The whole Lewisian approach of explaining things by mapping them strikes me as wrong.
11. Knowledge Aims / A. Knowledge / 1. Knowledge
In epistemology we should emphasis the continuity between animal and human minds [Russell]
     Full Idea: It seems to me desirable in the theory of knowledge to emphasise the continuity between animal and human minds.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.11)
     A reaction: I strongly agree with this, mainly because it avoids overemphasis on language in epistemology. It doesn't follow that animals know a lot, and there is a good case for saying that they don't actually 'know' anything, despite having true beliefs.
12. Knowledge Sources / D. Empiricism / 3. Pragmatism
Pragmatism judges by effects, but I judge truth by causes [Russell]
     Full Idea: Pragmatism holds that a belief is to be judged if it has certain effects, whereas I hold that an empirical belief is to be judged true if it has certain kinds of causes.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.15)
     A reaction: I'm with Russell here, and this seems to me a convincing objection to pragmatism. The simple problem is that falsehoods can occasionally have very beneficial effects. Beliefs are made true by the facts, not by their consequences.
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Empiricists seem unclear what they mean by 'experience' [Russell]
     Full Idea: When I began to think about theory of knowledge, I found that none of the philosophers who emphasise 'experience' tells us what they mean by the word.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.11)
     A reaction: A very significant comment about empiricism. Hume does not seem very clear about what an 'impression' is. Russell's problem has been dealt with intensively by modern empiricists, who discuss 'the given', and conceptualised perception.
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin]
     Full Idea: Against the Stoics, the Pyrrhonians argued that if someone presents a criterion of truth, then it will be important to determine whether it is the correct criterion.
     From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4
     A reaction: Hence Davidson says that attempts to define truth are 'folly'. If something has to be taken as basic, then truth seems a good candidate (since, for example, logical operators could not otherwise be defined by means of 'truth' tables).
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / b. Gettier problem
True belief about the time is not knowledge if I luckily observe a stopped clock at the right moment [Russell]
     Full Idea: Not all true beliefs are knowledge; the stock example to the contrary is that of a clock which has stopped by which I believe to be going and which I happen to look at when, by chance, it shows the right time.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.15)
     A reaction: [in his 1948:112] Russell had spotted Gettier-type problems long before Gettier. The problem of lucky true beliefs dates back to Plato (Idea 2140). This example is also a problem for reliabilism, if the clock is usually working fine.
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin]
     Full Idea: The attacks of the Pyrrhonian sceptics are directed against the dogmas of the 'professors', not against the beliefs of the common people pursuing the business of daily life.
     From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4
     A reaction: This may be because they thought that ordinary people were too confused to be worth attacking, rather than because they lived in a state of beautifully appropriate beliefs. Naďve realism is certainly worth attacking.
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin]
     Full Idea: The ancient Academic sceptics charged the Pyrrhonian sceptics with 'negative dogmatism' when they claimed that a certain kind of knowledge is impossible.
     From: report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4
     A reaction: It is this kind of point which should push us towards some sort of rationalism, because certain a priori 'dogmas' seem to be indispensable to get any sort of discussion off the ground. The only safe person is Cratylus (see Idea 578).
13. Knowledge Criteria / E. Relativism / 1. Relativism
Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius]
     Full Idea: Fifth mode: judgements vary according to local custom, law and culture (Persians marry their daughters).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius]
     Full Idea: Third mode: things like an apple vary according to which sense perceives them (yellow, sweet, and fragrant).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius]
     Full Idea: Seventh mode: perception varies according to viewing distance and angle (the sun, and a dove's neck).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius]
     Full Idea: Tenth mode: perceptions and judgements depend on comparison (light/heavy, above/below).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius]
     Full Idea: Second mode: individual men vary in responses and feelings (heat and cold, for example).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius]
     Full Idea: First mode: animals vary in their feelings and judgements (of food, for example).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius]
     Full Idea: Fourth mode: perceivers vary in their mental and physical state (such as the mad and the sick).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius]
     Full Idea: Eighth mode: perceptions of things depend on their magnitude or quantity (food and wine).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius]
     Full Idea: Sixth mode: the perception of an object depends on surrounding conditions (sunlight and lamplight).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius]
     Full Idea: Ninth mode: we perceive things according to what we expect (earthquakes and sunshine).
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Py.9
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
General truths are a type of negative truth, saying there are no more ravens than black ones [Armstrong]
     Full Idea: General truths are a species of negative truth, 'no more' truths, asserting that there are no more men than the mortal ones, no more ravens than the black ones.
     From: David M. Armstrong (Truth and Truthmakers [2004], 05.1)
     A reaction: He goes on to distinguish between 'absences' and 'limits' in this area.
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
Behaviourists struggle to explain memory and imagination, because they won't admit images [Russell]
     Full Idea: Behaviourists refuse to admit images because they cannot be observed from without, but this causes them difficulties when they attempt to explain either memory or imagination.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.13)
     A reaction: This is a striking objection to behaviourism, and it is rarely mentioned in modern discussions of the topic. They might try denying the existence of private 'images', but that wouldn't be very plausible.
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
Surprise is a criterion of error [Russell]
     Full Idea: Surprise is a criterion of error.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.15)
     A reaction: Russell is not too precise about this, but it is a nice point. Surprise is thwarted expectation, which implies prior misjudgement.
19. Language / A. Nature of Meaning / 5. Meaning as Verification
Unverifiable propositions about the remote past are still either true or false [Russell]
     Full Idea: There is no conceivable method by which we can discover whether the proposition 'It snowed on Manhattan Island on the 1st January in the year 1 A.D.' is true or false, but it seems preposterous to maintain that it is neither.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.10)
     A reaction: I love this example, which seems so simple and so clear-cut. It criticises verificationism, and gives strong intuitive support for realism, and supports the law of excluded middle.
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
For all being, there is a potential proposition which expresses its existence and nature [Armstrong]
     Full Idea: The thesis of 'expressibility' says that for all being, there is a proposition (perhaps one never formulated by any mind at any time) that truly renders the existence and nature of this being.
     From: David M. Armstrong (Truth and Truthmakers [2004], 02.3.2)
     A reaction: [He credits Stephen Read 2000:68-9 for this] Armstrong accepts this, but I deny it. I can't make any sense of this vast plethora of propositions, each exactly expressing some minute nuance of the infinity complexity of all being.
A realm of abstract propositions is causally inert, so has no explanatory value [Armstrong]
     Full Idea: We could not stand in any causal or nomic relation to a realm of propositions over and above the space-time world, ...so it is unclear that such a postulation is of any explanatory value.
     From: David M. Armstrong (Truth and Truthmakers [2004], 02.6)
     A reaction: I agree, and I like Armstrong's appeal to explanation as a criterion for whether we should make an ontological commitment here. I am baffled by anyone who thinks reality is crammed full of unarticulated propositions. Only a philosopher....
19. Language / D. Propositions / 4. Mental Propositions
You can believe the meaning of a sentence without thinking of the words [Russell]
     Full Idea: If you have just heard a loud clap of thunder, you believe what is expressed by 'there has just been a loud clap of thunder' even if no words come into your mind.
     From: Bertrand Russell (My Philosophical Development [1959], Ch.13)
     A reaction: This seems to me important, and accurate. We should not be too mesmerised by language. Animals have beliefs, and this is a nice example of an undeniable non-linguistic human belief.
26. Natural Theory / C. Causation / 4. Naturalised causation
Negative causations supervene on positive causations plus their laws? [Armstrong]
     Full Idea: Is it not very plausible that negative causations supervene on the positive causations together with the laws that govern the positive causations?
     From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.3)
     A reaction: This obviously has a naturalistic appeal, since all causation can then be based on the actual world.
26. Natural Theory / C. Causation / 7. Eliminating causation
There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius]
     Full Idea: The idea of cause is relative to that of which it is the cause, and so has no real existence. …Also cause must either be body causing body, or incorporeal causing incorporeal, and neither of these is possible.
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius]
     Full Idea: Motion is not moved in the place in which it is is, and it is impossible that it should be moved in the place in which it is not, so there is no such thing as motion.
     From: report of Pyrrho (reports [c.325 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.11.11
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
The pure present moment is too brief to be experienced [Armstrong]
     Full Idea: The metaphysical present will be a strict instant, or, if time is not infinitely divisible, the present will be a minimum granule of duration. But strict instants or minimal granules of duration, if these exist, cannot be experienced.
     From: David M. Armstrong (Truth and Truthmakers [2004], 11)
     A reaction: He points out that this is ironic, since Presentism lies on the basic experience of the present.