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43 ideas

1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Super-ordinate disciplines give laws or principles; subordinate disciplines give concrete cases [Peirce, by Atkin]
     Full Idea: In Peirce's system, a super-ordinate discipline provides general laws or principles for subordinate disciplines, which in turn provide concrete examples of those general laws.
     From: report of Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 1 'System'
     A reaction: Does he really mean that subordinate disciplines have no principles or laws? That can't be right.
2. Reason / A. Nature of Reason / 3. Pure Reason
The logical space of reasons is a natural phenomenon, and it is the realm of freedom [McDowell]
     Full Idea: The logical space of reasons is just part of the logical space of nature. ...And, in a Kantian slogan, the space of reasons is the realm of freedom.
     From: John McDowell (Mind and World [1994], Intro 7)
     A reaction: [second half on p.5] This is a modern have-your-cake-and-eat-it view of which I am becoming very suspicious. The modern Kantians (Davidson, Nagel, McDowell) are struggling to naturalise free will, but it won't work. Just dump it!
2. Reason / D. Definition / 7. Contextual Definition
A contextual definition permits the elimination of the expression by a substitution [Dummett]
     Full Idea: The standard sense of a 'contextual definition' permits the eliminating of the defined expression, by transforming any sentence containing it into an equivalent one not containing it.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.11)
     A reaction: So the whole definition might be eliminated by a single word, which is not equivalent to the target word, which is embedded in the original expression. Clearly contextual definitions have some problems
3. Truth / E. Pragmatic Truth / 1. Pragmatic Truth
Pragmatic 'truth' is a term to cover the many varied aims of enquiry [Peirce, by Misak]
     Full Idea: In Peirce's naturalist view of truth, it is a catch-all for the particular local aims of enquiry - empirical adequacy, predictive power, coherence, simplicity, elegance, explanatory power, a reliable guide to action, fruitfulness, great understanding.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 1
     A reaction: The aims I cited in my thesis on explanation. One given, for me, is that truth is an ideal, which may or may not be attainable, to varying degrees. It is just what thinking aims at. I suspect, though, that these listed items have one thing in common.
Peirce did not think a belief was true if it was useful [Peirce, by Misak]
     Full Idea: Peirce was not in the slightest bit tempted by the thought that a belief is true if it is useful.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 2
     A reaction: All students of the pragmatic theory of truth should start with this idea, because it rejects the caricature view of pragmatic truth, a view which is easily rebutted. James seems to have been guilty of this sin.
If truth is the end of enquiry, what if it never ends, or ends prematurely? [Atkin on Peirce]
     Full Idea: Two related worries about Peirce's account of truth are (from Royce) what are we to make of truth if enquiry never reaches an end, and (from Russell) what are we to make of truth if enquiry ends prematurely?
     From: comment on Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 3 'issues'
     A reaction: The defence of Peirce must be that the theory is not holistic - referring to the whole Truth about absolutely everything. The discovery of the periodic table seems to me to support Peirce. In many areas basic enquiry has reached an end.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
In classical logic, logical truths are valid formulas; in higher-order logics they are purely logical [Dummett]
     Full Idea: For sentential or first-order logic, the logical truths are represented by valid formulas; in higher-order logics, by sentences formulated in purely logical terms.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 3)
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Pure mathematics deals only with hypotheses, of which the reality does not matter [Peirce]
     Full Idea: The pure mathematician deals exclusively with hypotheses. Whether or not there is any corresponding real thing, he does not care.
     From: Charles Sanders Peirce (works [1892], CP5.567), quoted by Albert Atkin - Peirce 3 'separation'
     A reaction: [Dated 1902] Maybe we should identify a huge branch of human learning as Hyptheticals. Professor of Hypotheticals at Cambridge University. The trouble is it would have to include computer games. So why does maths matter more than games?
5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
Bivalence is a regulative assumption of enquiry - not a law of logic [Peirce, by Misak]
     Full Idea: Peirce takes bivalence not to be a law of logic, but a regulative assumption of enquiry.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 2 n10
     A reaction: I like this. For most enquiries it's either true or not true, it's either there or it's not there. When you aren't faced with these simple dichotomies (in history, or quantum mechanics) you can relax, and allow truth value gaps etc.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
A prime number is one which is measured by a unit alone [Dummett]
     Full Idea: A prime number is one which is measured by a unit alone.
     From: Michael Dummett (Frege philosophy of mathematics [1991], 7 Def 11)
     A reaction: We might say that the only way of 'reaching' or 'constructing' a prime is by incrementing by one till you reach it. That seems a pretty good definition. 64, for example, can be reached by a large number of different routes.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Addition of quantities is prior to ordering, as shown in cyclic domains like angles [Dummett]
     Full Idea: It is essential to a quantitative domain of any kind that there should be an operation of adding its elements; that this is more fundamental thaat that they should be linearly ordered by magnitude is apparent from cyclic domains like that of angles.
     From: Michael Dummett (Frege philosophy of mathematics [1991], 22 'Quantit')
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / a. Units
A number is a multitude composed of units [Dummett]
     Full Idea: A number is a multitude composed of units.
     From: Michael Dummett (Frege philosophy of mathematics [1991], 7 Def 2)
     A reaction: This is outdated by the assumption that 0 and 1 are also numbers, but if we say one is really just the 'unit' which is preliminary to numbers, and 0 is as bogus a number as i is, we might stick with the original Greek distinction.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / e. Counting by correlation
We understand 'there are as many nuts as apples' as easily by pairing them as by counting them [Dummett]
     Full Idea: A child understands 'there are just as many nuts as apples' as easily by pairing them off as by counting them.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12)
     A reaction: I find it very intriguing that you could know that two sets have the same number, without knowing any numbers. Is it like knowing two foreigners spoke the same words, without understanding them? Or is 'equinumerous' conceptually prior to 'number'?
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
The identity of a number may be fixed by something outside structure - by counting [Dummett]
     Full Idea: The identity of a mathematical object may sometimes be fixed by its relation to what lies outside the structure to which it belongs. It is more fundamental to '3' that if certain objects are counted, there are three of them.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 5)
     A reaction: This strikes me as Dummett being pushed (by his dislike of the purely abstract picture given by structuralism) back to a rather empiricist and physical view of numbers, though he would totally deny that.
Numbers aren't fixed by position in a structure; it won't tell you whether to start with 0 or 1 [Dummett]
     Full Idea: The number 0 is not differentiated from 1 by its position in a progression, otherwise there would be no difference between starting with 0 and starting with 1. That is enough to show that numbers are not identifiable just as positions in structures.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 5)
     A reaction: This sounds conclusive, but doesn't feel right. If numbers are a structure, then where you 'start' seems unimportant. Where do you 'start' in St Paul's Cathedral? Starting sounds like a constructivist concept for number theory.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Set theory isn't part of logic, and why reduce to something more complex? [Dummett]
     Full Idea: The two frequent modern objects to logicism are that set theory is not part of logic, or that it is of no interest to 'reduce' a mathematical theory to another, more complex, one.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18)
     A reaction: Dummett says these are irrelevant (see context). The first one seems a good objection. The second one less so, because whether something is 'complex' is a quite different issue from whether it is ontologically more fundamental.
7. Existence / C. Structure of Existence / 7. Abstract/Concrete / a. Abstract/concrete
The distinction of concrete/abstract, or actual/non-actual, is a scale, not a dichotomy [Dummett]
     Full Idea: The distinction between concrete and abstract objects, or Frege's corresponding distinction between actual and non-actual objects, is not a sharp dichotomy, but resembles a scale upon which objects occupy a range of positions.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18)
     A reaction: This might seem right if you live (as Dummett chooses to) in the fog of language, but it surely can't be right if you think about reality. Is the Equator supposed to be near the middle of his scale? Either there is an equator, or there isn't.
7. Existence / D. Theories of Reality / 2. Realism
Realism is just the application of two-valued semantics to sentences [Dummett]
     Full Idea: Fully fledged realism depends on - indeed, may be identified with - an undiluted application to sentences of the relevant kind of straightforwards two-valued semantics.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15)
     A reaction: This is the sort of account you get from a whole-heartedly linguistic philosopher. Personally I would say that Dummett has got it precisely the wrong way round: I adopt a two-valued semantics because my metaphysics is realist.
7. Existence / D. Theories of Reality / 3. Reality
The real is the idea in which the community ultimately settles down [Peirce]
     Full Idea: The real is the idea in which the community ultimately settles down.
     From: Charles Sanders Peirce (works [1892]), quoted by Martin Kusch - Knowledge by Agreement Ch.16
     A reaction: If this is anti-realism, then I don't like it. If it is realist, then it is probably a bit on the optimistic side (if you think about cultures that are into witchcraft and voodoo).
8. Modes of Existence / A. Relations / 1. Nature of Relations
Peirce and others began the mapping out of relations [Peirce, by Hart,WD]
     Full Idea: It was Peirce and Schröder in the nineteenth century who began a systematic taxonomy of relations.
     From: report of Charles Sanders Peirce (works [1892], 4) by William D. Hart - The Evolution of Logic 4
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / d. Dispositions as occurrent
Peirce's later realism about possibilities and generalities went beyond logical positivism [Peirce, by Atkin]
     Full Idea: The realism about possibilities, generalities, tendencies and habits that we find in Peirce's later maxim is something that the logical positivists would have been uncomfortable with.
     From: report of Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 2 'Concl'
     A reaction: Atkin examines the various later statements of the earlier maxim, given here in Idea 21490. Ryle and Quine express the empiricist and logical positivist approach to dispositions.
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
Nominalism assumes unmediated mental contact with objects [Dummett]
     Full Idea: The nominalist superstition is based ultimately on the myth of the unmediated presentation of genuine concrete objects to the mind.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18)
     A reaction: Personally I am inclined to favour nominalism and a representative theory of perception, which acknowledges some 'mediation', but of a non-linguistic form. Any good theory here had better include animals, which seem to form concepts.
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
The existence of abstract objects is a pseudo-problem [Dummett]
     Full Idea: The existence of abstract objects is a pseudo-problem.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.18)
     A reaction: This remark follows after Idea 9884, which says the abstract/concrete distinction is a sliding scale. Personally I take the distinction to be fairly sharp, and it is therefore probably the single most important problem in the whole of human thought.
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
Abstract objects nowadays are those which are objective but not actual [Dummett]
     Full Idea: Objects which are objective but not actual are precisely what are now called abstract objects.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15)
     A reaction: Why can there not be subjective abstract objects? 'My favourites are x, y and z'. 'I'll decide later what my favourites are'. 'I only buy my favourites - nothing else'.
It is absurd to deny the Equator, on the grounds that it lacks causal powers [Dummett]
     Full Idea: If someone argued that assuming the existence of the Equator explains nothing, and it has no causal powers, so everything would be the same if it didn't exist, so we needn't accept its existence, we should gape at the crudity of the misunderstanding.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15)
     A reaction: Not me. I would gape if someone argued that latitude 55° 14' (and an infinity of other lines) exists for the same reasons (whatever they may be) that the Equator exists. A mode of description can't create an object.
'We've crossed the Equator' has truth-conditions, so accept the Equator - and it's an object [Dummett]
     Full Idea: 'We've crossed the Equator' is judged true if we are nearer the other Pole, so it not for philosophers to deny that the Earth has an equator, and we see that the Equator is not a concept or relation or function, so it must be classified as an object.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.15)
     A reaction: A lovely example of linguistic philosophy in action (and so much the worse for that, I would say). A useful label here, I suggest (unoriginally, I think), is that we should label such an item a 'semantic object', rather than a real object in our ontology.
9. Objects / A. Existence of Objects / 2. Abstract Objects / d. Problems with abstracta
Abstract objects need the context principle, since they can't be encountered directly [Dummett]
     Full Idea: To recognise that there is no objection in principle to abstract objects requires acknowledgement that some form of the context principle is correct, since abstract objects can neither be encountered nor presented.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.16)
     A reaction: I take this to be an immensely important idea. I consider myself to be a philosopher of thought rather than a philosopher of language (Dummett's distinction, he being one of the latter). Thought connects to the world, but does it connect to abstracta?
9. Objects / F. Identity among Objects / 2. Defining Identity
Content is replaceable if identical, so replaceability can't define identity [Dummett, by Dummett]
     Full Idea: Husserl says the only ground for assuming the replaceability of one content by another is their identity; we are therefore not entitled to define their identity as consisting in their replaceability.
     From: report of Michael Dummett (Frege philosophy of mathematics [1991]) by Michael Dummett - Frege philosophy of mathematics Ch.12
     A reaction: This is a direct challenge to Frege. Tricky to arbitrate, as it is an issue of conceptual priority. My intuition is with Husserl, but maybe the two are just benignly inerdefinable.
Frege introduced criteria for identity, but thought defining identity was circular [Dummett]
     Full Idea: In his middle period Frege rated identity indefinable, on the ground that every definition must take the form of an identity-statement. Frege introduced the notion of criterion of identity, which has been widely used by analytical philosophers.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.10)
     A reaction: The objection that attempts to define identity would be circular sounds quite plausible. It sounds right to seek a criterion for type-identity (in shared properties or predicates), but token-identity looks too fundamental to give clear criteria.
10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
The possible can only be general, and the force of actuality is needed to produce a particular [Peirce]
     Full Idea: The possible is necessarily general…..It is only actuality, the force of existence, which bursts the fluidity of the general and produces a discrete unit.
     From: Charles Sanders Peirce (works [1892]), quoted by François Recanati - Mental Files 13.1
     A reaction: [Papers 4 1967:147] This was quoted by Prior, and is often cited. Recanati is interested in the notion of a singular thought being tied to actuality, by generating a mental file.
11. Knowledge Aims / B. Certain Knowledge / 3. Fallibilism
Inquiry is not standing on bedrock facts, but standing in hope on a shifting bog [Peirce]
     Full Idea: Inquiry is not standing upon a bedrock of fact. It is walking up a bog, and can only say, this ground seems to hold for the present. Here I will stay until it begins to give way.
     From: Charles Sanders Peirce (works [1892], CP 5.589), quoted by Gottfried Leibniz - Letter to Newton 4
     A reaction: [I don't know which article this lovely quote comes from]
12. Knowledge Sources / B. Perception / 3. Representation
Representation must be propositional if it can give reasons and be epistemological [McDowell, by Burge]
     Full Idea: McDowell has claimed that one cannot make sense of representation that plays a role in epistemology unless one takes the representation to be propositional, and thus capable of yielding reasons.
     From: report of John McDowell (Mind and World [1994]) by Tyler Burge - Philosophy of Mind: 1950-2000 p.456
     A reaction: A transcendental argument leads back to a somewhat implausible conclusion. I suspect that McDowell has a slightly inflated (Kantian) notion of the purity of the 'space of reasons'. Do philosophers just imagine their problems?
12. Knowledge Sources / B. Perception / 5. Interpretation
There is no pure Given, but it is cultured, rather than entirely relative [McDowell, by Macbeth]
     Full Idea: McDowell argues that the Myth of the Given shows not that there is no content to a concept that is not a matter of its inferential relations to other concepts but only that awareness of the sort that we enjoy ...is acquired in the course of acculturation.
     From: report of John McDowell (Mind and World [1994]) by Danielle Macbeth - Pragmatism and Objective Truth p.185
     A reaction: The first view is of Wilfred Sellars, who derives pragmatic relativism from his rejection of the Myth. This idea is helpful is seeing why McDowell has a good proposal. As I look out of my window, my immediate experience seems 'cultured'.
12. Knowledge Sources / D. Empiricism / 1. Empiricism
Sense impressions already have conceptual content [McDowell]
     Full Idea: The world's impressions on our senses are already possessed of conceptual content.
     From: John McDowell (Mind and World [1994], I.6)
     A reaction: This is a key idea of McDowell's, which challenges most traditional empiricist views, and (maybe) offers a solution to the rationalist/empiricist debate. His commitment to the 'space of reasons' strikes me as an optional extra.
18. Thought / D. Concepts / 4. Structure of Concepts / i. Conceptual priority
Maybe a concept is 'prior' to another if it can be defined without the second concept [Dummett]
     Full Idea: One powerful argument for a thesis that one notion is conceptually prior to another is the possibility of defining the first without reference to the second.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12)
     A reaction: You'd better check whether you can't also define the second without reference to the first before you rank their priority. And maybe 'conceptual priority' is conceptually prior to 'definition' (i.e. definition needs a knowledge of priority). Help!
An argument for conceptual priority is greater simplicity in explanation [Dummett]
     Full Idea: An argument for conceptual priority is greater simplicity in explanation.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.12)
     A reaction: One might still have to decide priority between two equally simple (or complex) concepts. I begin to wonder whether 'priority' has any other than an instrumental meaning (according to which direction you wish to travel - is London before Edinburgh?).
18. Thought / E. Abstraction / 1. Abstract Thought
Abstract terms are acceptable as long as we know how they function linguistically [Dummett]
     Full Idea: To recognise abstract terms as perfectly proper items of a vocabulary depends upon allowing that all that is necessary for the lawful introduction of a range of expressions into the language is a coherent account of how they are to function in sentences.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.16)
     A reaction: Why can't the 'coherent account' of the sentences include the fact that there must be something there for the terms to refer to? How else are we to eliminate nonsense words which obey good syntactical rules? Cf. Idea 9872.
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
There is no reason why abstraction by equivalence classes should be called 'logical' [Dummett, by Tait]
     Full Idea: Dummett uses the term 'logical abstraction' for the construction of the abstract objects as equivalence classes, but it is not clear why we should call this construction 'logical'.
     From: report of Michael Dummett (Frege philosophy of mathematics [1991]) by William W. Tait - Frege versus Cantor and Dedekind n 14
     A reaction: This is a good objection, and Tait offers a much better notion of 'logical abstraction' (as involving preconditions for successful inference), in Idea 9981.
We arrive at the concept 'suicide' by comparing 'Cato killed Cato' with 'Brutus killed Brutus' [Dummett]
     Full Idea: We arrive at the concept of suicide by considering both occurrences in the sentence 'Cato killed Cato' of the proper name 'Cato' as simultaneously replaceable by another name, say 'Brutus', and so apprehending the pattern common to both sentences.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch.14)
     A reaction: This is intended to illustrate Frege's 'logical abstraction' technique, as opposed to wicked psychological abstraction. The concept of suicide is the pattern 'x killed x'. This is a crucial example if we are to understand abstraction...
18. Thought / E. Abstraction / 8. Abstractionism Critique
To abstract from spoons (to get the same number as the forks), the spoons must be indistinguishable too [Dummett]
     Full Idea: To get units by abstraction, units arrived at by abstraction from forks must the identical to that abstracted from spoons, with no trace of individuality. But if spoons can no longer be differentiated from forks, they can't differ from one another either.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 8)
     A reaction: [compressed] Dummett makes the point better than Frege did. Can we 'think of a fork insofar as it is countable, ignoring its other features'? What are we left thinking of? Frege says it must still be the whole fork. 'Nice fork, apart from the colour'.
19. Language / C. Assigning Meanings / 5. Fregean Semantics
Fregean semantics assumes a domain articulated into individual objects [Dummett]
     Full Idea: A Fregean semantics assumes a domain already determinately articulated into individual objects.
     From: Michael Dummett (Frege philosophy of mathematics [1991], Ch. 8)
     A reaction: A more interesting criticism than most of Dummett's other challenges to the Frege/Davidson view. I am beginning to doubt whether the semantics and the ontology can ever be divorced from the psychology, of thought, interests, focus etc.
19. Language / F. Communication / 4. Private Language
Forming concepts by abstraction from the Given is private definition, which the Private Lang. Arg. attacks [McDowell]
     Full Idea: The idea that concepts can be formed by abstraction from the Given just is the idea of private ostensive definition. So the Private Language Argument just is the rejection of the Given, in so far as it bears on the possibilities for language.
     From: John McDowell (Mind and World [1994], I.7)
     A reaction: I'm not clear why the process of abstraction from raw impressions shouldn't be a matter of public, explicit, community negotiation. We seem to be able to share and compare fairly raw impressions without much trouble (discussing sunsets).
27. Natural Reality / C. Space / 3. Points in Space
Why should the limit of measurement be points, not intervals? [Dummett]
     Full Idea: By what right do we assume that the limit of measurement is a point, and not an interval?
     From: Michael Dummett (Frege philosophy of mathematics [1991], 22 'Quantit')