Combining Texts

All the ideas for 'Thinking About Mathematics', 'Contrib to Critique of Hegel's Phil of Right' and 'The Coherence Theory of Truth'

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


27 ideas

3. Truth / B. Truthmakers / 12. Rejecting Truthmakers
For idealists reality is like a collection of beliefs, so truths and truthmakers are not distinct [Young,JO]
     Full Idea: Idealists do not believe that there is an ontological distinction between beliefs and what makes beliefs true. From their perspective, reality is something like a collection of beliefs.
     From: James O. Young (The Coherence Theory of Truth [2013], §2.1)
     A reaction: This doesn't seem to me to wholly reject truthmakers, since beliefs can still be truthmakers for one another. This is something like Davidson's view, that only beliefs can justify other beliefs.
3. Truth / D. Coherence Truth / 1. Coherence Truth
Coherence theories differ over the coherence relation, and over the set of proposition with which to cohere [Young,JO]
     Full Idea: Coherence theories of truth differ on their accounts of the coherence relation, and on their accounts of the set (or sets) of propositions with which true propositions occur (the 'specified set').
     From: James O. Young (The Coherence Theory of Truth [2013], §1)
     A reaction: Coherence is clearly more than consistency or mutual entailment, and I like to invoke explanation. The set has to be large, or the theory is absurd (as two absurdities can 'cohere'). So very large, or very very large, or maximally large?
Two propositions could be consistent with your set, but inconsistent with one another [Young,JO]
     Full Idea: It is unsatisfactory for the coherence relation to be consistency, because two propositions could be consistent with a 'specified set', and yet be inconsistent with each other. That would imply they are both true, which is impossible.
     From: James O. Young (The Coherence Theory of Truth [2013], §1)
     A reaction: I'm not convinced by this. You first accept P because it is consistent with the set; then Q turns up, which is consistent with everything in the set except P. So you have to choose between them, and might eject P. Your set was too small.
Coherence with actual beliefs, or our best beliefs, or ultimate ideal beliefs? [Young,JO]
     Full Idea: One extreme for the specified set is the largest consistent set of propositions currently believed by actual people. A moderate position makes it the limit of people's enquiries. The other extreme is what would be believed by an omniscient being.
     From: James O. Young (The Coherence Theory of Truth [2013], §1)
     A reaction: One not considered is the set of propositions believed by each individual person. Thoroughgoing relativists might well embrace that one. Peirce and Putnam liked the moderate one. I'm taken with the last one, since truth is an ideal, not a phenomenon.
Coherent truth is not with an arbitrary set of beliefs, but with a set which people actually do believe [Young,JO]
     Full Idea: It must be remembered that coherentists do not believe that the truth of a proposition consists in coherence with an arbitrarily chosen set of propositions; the coherence is with a set of beliefs, or a set of propositions held to be true.
     From: James O. Young (The Coherence Theory of Truth [2013], §3.1)
     A reaction: This is a very good response to critics who cite bizarre sets of beliefs which happen to have internal coherence. You have to ask why they are not actually believed, and the answer must be that the coherence is not extensive enough.
3. Truth / D. Coherence Truth / 2. Coherence Truth Critique
How do you identify the best coherence set; and aren't there truths which don't cohere? [Young,JO]
     Full Idea: The two main objections to the coherence theory of truth are that there is no way to identify the 'specified set' of propositions without contradiction, ...and that some propositions are true which cohere with no set of beliefs.
     From: James O. Young (The Coherence Theory of Truth [2013], §3.1/2)
     A reaction: The point of the first is that you need a prior knowledge of truth to say which of two sets is the better one. The second one is thinking of long-lost tiny details from the past, which seem to be true without evidence. A huge set might beat the first one.
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Deflationary theories reject analysis of truth in terms of truth-conditions [Young,JO]
     Full Idea: Unlike deflationary theories, the coherence and correspondence theories both hold that truth is a property of propositions that can be analyzed in terms of the sorts of truth-conditions propositions have, and the relation propositions stand in to them.
     From: James O. Young (The Coherence Theory of Truth [2013], Intro)
     A reaction: This is presumably because deflationary theories reject the external relations of a proposition as a feature of its truth. This evidently leaves them in need of a theory of meaning, which may be fairly minimal. Horwich would be an example.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Intuitionists deny excluded middle, because it is committed to transcendent truth or objects [Shapiro]
     Full Idea: Intuitionists in mathematics deny excluded middle, because it is symptomatic of faith in the transcendent existence of mathematical objects and/or the truth of mathematical statements.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 1.2)
     A reaction: There are other problems with excluded middle, such as vagueness, but on the whole I, as a card-carrying 'realist', am committed to the law of excluded middle.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
The number 3 is presumably identical as a natural, an integer, a rational, a real, and complex [Shapiro]
     Full Idea: It is surely wise to identify the positions in the natural numbers structure with their counterparts in the integer, rational, real and complex number structures.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 10.2)
     A reaction: The point is that this might be denied, since 3, 3/1, 3.00.., and -3*i^2 are all arrived at by different methods of construction. Natural 3 has a predecessor, but real 3 doesn't. I agree, intuitively, with Shapiro. Russell (1919) disagreed.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
Cauchy gave a formal definition of a converging sequence. [Shapiro]
     Full Idea: A sequence a1,a2,... of rational numbers is 'Cauchy' if for each rational number ε>0 there is a natural number N such that for all natural numbers m, n, if m>N and n>N then -ε < am - an < ε.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 7.2 n4)
     A reaction: The sequence is 'Cauchy' if N exists.
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Categories are the best foundation for mathematics [Shapiro]
     Full Idea: There is a dedicated contingent who hold that the category of 'categories' is the proper foundation for mathematics.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 10.3 n7)
     A reaction: He cites Lawvere (1966) and McLarty (1993), the latter presenting the view as a form of structuralism. I would say that the concept of a category will need further explication, and probably reduce to either sets or relations or properties.
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
Two definitions of 3 in terms of sets disagree over whether 1 is a member of 3 [Shapiro]
     Full Idea: Zermelo said that for each number n, its successor is the singleton of n, so 3 is {{{null}}}, and 1 is not a member of 3. Von Neumann said each number n is the set of numbers less than n, so 3 is {null,{null},{null,{null}}}, and 1 is a member of 3.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 10.2)
     A reaction: See Idea 645 - Zermelo could save Plato from the criticisms of Aristotle! These two accounts are cited by opponents of the set-theoretical account of numbers, because it seems impossible to arbitrate between them.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Numbers do not exist independently; the essence of a number is its relations to other numbers [Shapiro]
     Full Idea: The structuralist vigorously rejects any sort of ontological independence among the natural numbers; the essence of a natural number is its relations to other natural numbers.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 10.1)
     A reaction: This seems to place the emphasis on ordinals (what order?) rather than on cardinality (how many?). I am strongly inclined to think that this is the correct view, though you can't really have relations if there is nothing to relate.
A 'system' is related objects; a 'pattern' or 'structure' abstracts the pure relations from them [Shapiro]
     Full Idea: A 'system' is a collection of objects with certain relations among them; a 'pattern' or 'structure' is the abstract form of a system, highlighting the interrelationships and ignoring any features they do not affect how they relate to other objects.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 10.1)
     A reaction: Note that 'ignoring' features is a psychological account of abstraction, which (thanks to Frege and Geach) is supposed to be taboo - but which I suspect is actually indispensable in any proper account of thought and concepts.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logicism seems to be a non-starter if (as is widely held) logic has no ontology of its own [Shapiro]
     Full Idea: The thesis that principles of arithmetic are derivable from the laws of logic runs against a now common view that logic itself has no ontology. There are no particular logical objects. From this perspective logicism is a non-starter.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 5.1)
     A reaction: This criticism strikes me as utterly devastating. There are two routes to go: prove that logic does have an ontology of objects (what would they be?), or - better - deny that arithmetic contains any 'objects'. Or give up logicism.
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Term Formalism says mathematics is just about symbols - but real numbers have no names [Shapiro]
     Full Idea: Term Formalism is the view that mathematics is just about characters or symbols - the systems of numerals and other linguistic forms. ...This will cover integers and rational numbers, but what are real numbers supposed to be, if they lack names?
     From: Stewart Shapiro (Thinking About Mathematics [2000], 6.1.1)
     A reaction: Real numbers (such as pi and root-2) have infinite decimal expansions, so we can start naming those. We could also start giving names like 'Harry' to other reals, though it might take a while. OK, I give up.
Game Formalism is just a matter of rules, like chess - but then why is it useful in science? [Shapiro]
     Full Idea: Game Formalism likens mathematics to chess, where the 'content' of mathematics is exhausted by the rules of operating with its language. ...This, however, leaves the problem of why the mathematical games are so useful to the sciences.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 6.1.2)
     A reaction: This thought pushes us towards structuralism. It could still be a game, but one we learned from observing nature, which plays its own games. Chess is, after all, modelled on warfare.
Deductivism says mathematics is logical consequences of uninterpreted axioms [Shapiro]
     Full Idea: The Deductivist version of formalism (sometimes called 'if-thenism') says that the practice of mathematics consists of determining logical consequences of otherwise uninterpreted axioms.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 6.2)
     A reaction: [Hilbert is the source] More plausible than Term or Game Formalism (qv). It still leaves the question of why it seems applicable to nature, and why those particular axioms might be chosen. In some sense, though, it is obviously right.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Critics resent the way intuitionism cripples mathematics, but it allows new important distinctions [Shapiro]
     Full Idea: Critics commonly complain that the intuitionist restrictions cripple the mathematician. On the other hand, intuitionist mathematics allows for many potentially important distinctions not available in classical mathematics, and is often more subtle.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 7.1)
     A reaction: The main way in which it cripples is its restriction on talk of infinity ('Cantor's heaven'), which was resented by Hilbert. Since high-level infinities are interesting, it would be odd if we were not allowed to discuss them.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / c. Conceptualism
Conceptualist are just realists or idealist or nominalists, depending on their view of concepts [Shapiro]
     Full Idea: I classify conceptualists according to what they say about properties or concepts. If someone classified properties as existing independent of language I would classify her as a realist in ontology of mathematics. Or they may be idealists or nominalists.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 2.2.1)
     A reaction: In other words, Shapiro wants to eliminate 'conceptualist' as a useful label in philosophy of mathematics. He's probably right. All thought involves concepts, but that doesn't produce a conceptualist theory of, say, football.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
'Impredicative' definitions refer to the thing being described [Shapiro]
     Full Idea: A definition of a mathematical entity is 'impredicative' if it refers to a collection that contains the defined entity. The definition of 'least upper bound' is impredicative as it refers to upper bounds and characterizes a member of this set.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 1.2)
     A reaction: The big question is whether mathematics can live with impredicative definitions, or whether they threaten to be viciously circular, and undermine the whole enterprise.
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Rationalism tries to apply mathematical methodology to all of knowledge [Shapiro]
     Full Idea: Rationalism is a long-standing school that can be characterized as an attempt to extend the perceived methodology of mathematics to all of knowledge.
     From: Stewart Shapiro (Thinking About Mathematics [2000], 1.1)
     A reaction: Sometimes called 'Descartes's Dream', or the 'Enlightenment Project', the dream of proving everything. Within maths, Hilbert's Programme aimed for the same certainty. Idea 22 is the motto for the opposition to this approach.
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Are truth-condtions other propositions (coherence) or features of the world (correspondence)? [Young,JO]
     Full Idea: For the coherence theory of truth, the truth conditions of propositions consist in other propositions. The correspondence theory, in contrast, states that the truth conditions of propositions are ... objective features of the world.
     From: James O. Young (The Coherence Theory of Truth [2013], Intro)
     A reaction: It is obviously rather important for your truth-conditions theory of meaning that you are clear about your theory of truth. A correspondence theory is evidently taken for granted, even in possible worlds versions.
Coherence truth suggests truth-condtions are assertion-conditions, which need knowledge of justification [Young,JO]
     Full Idea: Coherence theorists can argue that the truth conditions of a proposition are those under which speakers tend to assert it, ...and that speakers can only make a practice of asserting a proposition under conditions they can recognise as justifying it.
     From: James O. Young (The Coherence Theory of Truth [2013], §2.2)
     A reaction: [compressed] This sounds rather verificationist, and hence wrong, since if you then asserted anything for which you didn't know the justification, that would remove its truth, and thus make it meaningless.
24. Political Theory / C. Ruling a State / 4. Changing the State / c. Revolution
The middle class gain freedom through property, but workers can only free all of humanity [Marx, by Singer]
     Full Idea: Where the middle class can win freedom for themselves on the basis of rights to property - thus excluding others from their freedom - the working class have nothing but their title as human beings. They only liberate themselves by liberating humanity.
     From: report of Karl Marx (Contrib to Critique of Hegel's Phil of Right [1844]) by Peter Singer - Marx 4
     A reaction: Individual workers might gain freedom via education, marriage, or entrepreneurship, or by opting for total simplicity of life, but in general Marx seems to be right about this. But we must ask what sort of 'freedom' is needed.
Theory is as much a part of a revolution as material force is [Marx]
     Full Idea: Material force must be overthrown by material force. But theory also becomes a material force once it has gripped the masses.
     From: Karl Marx (Contrib to Critique of Hegel's Phil of Right [1844], Intro p.69), quoted by Peter Singer - Marx 4
     A reaction: A huge problem, I think, is that every theory (even conservatism) has to be simplified in a democracy if it is to grip the imagination of the majority. My current hatred is labels in political philosophy. They give us a cartoon view of the world.
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
Religion is the opium of the people, and real happiness requires its abolition [Marx]
     Full Idea: Religion is the opium of the people. The abolition of religion as the illusory happiness of the people is required for their real happiness.
     From: Karl Marx (Contrib to Critique of Hegel's Phil of Right [1844], Intro)
     A reaction: Not being religious myself, I have some sympathy with this ringing clarion-call. However, while opium satisfies an artificial and superficial need, religion certainly seems to speak to something deeper and more central in people.