Combining Texts

All the ideas for 'Classical Cosmology (frags)', 'In Defence of Pure Reason' and 'The Foundations of Mathematics'

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24 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophy is a priori if it is anything [Bonjour]
     Full Idea: My conviction is that philosophy is a priori if it is anything.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], Pref)
     A reaction: How about knowledge of a posteriori necessities, such as the length of a metre, known by observation of the standard metre in Paris?
2. Reason / A. Nature of Reason / 3. Pure Reason
Perceiving necessary connections is the essence of reasoning [Bonjour]
     Full Idea: If one never in fact grasps any necessary connections between anything, it is hard to see what reasoning could possible amount to.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §4.3)
2. Reason / A. Nature of Reason / 6. Coherence
Coherence can't be validated by appeal to coherence [Bonjour]
     Full Idea: The epistemic authority of coherence cannot itself be established by appeal to coherence.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §3.7 n50)
     A reaction: The standard approach amongs modern philosophers (following, I think, Kripke) is to insist on 'intuition' as basic, despite all its problems. I have no better suggestion.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
Infinity: there is an infinity of distinguishable individuals [Ramsey]
     Full Idea: The Axiom of Infinity means that there are an infinity of distinguishable individuals, which is an empirical proposition.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], §5)
     A reaction: The Axiom sounds absurd, as a part of a logical system, but Ramsey ends up defending it. Logical tautologies, which seem to be obviously true, are rendered absurd if they don't refer to any objects, and some of them refer to infinities of objects.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Reducibility: to every non-elementary function there is an equivalent elementary function [Ramsey]
     Full Idea: The Axiom of Reducibility asserted that to every non-elementary function there is an equivalent elementary function [note: two functions are equivalent when the same arguments render them both true or both false].
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], §2)
     A reaction: Ramsey in the business of showing that this axiom from Russell and Whitehead is not needed. He says that the axiom seems to be needed for induction and for Dedekind cuts. Since the cuts rest on it, and it is weak, Ramsey says it must go.
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Either 'a = b' vacuously names the same thing, or absurdly names different things [Ramsey]
     Full Idea: In 'a = b' either 'a' and 'b' are names of the same thing, in which case the proposition says nothing, or of different things, in which case it is absurd. In neither case is it an assertion of a fact; it only asserts when a or b are descriptions.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], §1)
     A reaction: This is essentially Frege's problem with Hesperus and Phosphorus. How can identities be informative? So 2+2=4 is extensionally vacuous, but informative because they are different descriptions.
5. Theory of Logic / L. Paradox / 1. Paradox
Contradictions are either purely logical or mathematical, or they involved thought and language [Ramsey]
     Full Idea: Group A consists of contradictions which would occur in a logical or mathematical system, involving terms such as class or number. Group B contradictions are not purely logical, and contain some reference to thought, language or symbolism.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], p.171), quoted by Graham Priest - The Structure of Paradoxes of Self-Reference 1
     A reaction: This has become the orthodox division of all paradoxes, but the division is challenged by Priest (Idea 13373). He suggests that we now realise (post-Tarski?) that language is more involved in logic and mathematics than we thought.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Formalists neglect content, but the logicists have focused on generalizations, and neglected form [Ramsey]
     Full Idea: The formalists neglected the content altogether and made mathematics meaningless, but the logicians neglected the form and made mathematics consist of any true generalisations; only by taking account of both sides can we obtain an adequate theory.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], §1)
     A reaction: He says mathematics is 'tautological generalizations'. It is a criticism of modern structuralism that it overemphasises form, and fails to pay attention to the meaning of the concepts which stand at the 'nodes' of the structure.
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Formalism is hopeless, because it focuses on propositions and ignores concepts [Ramsey]
     Full Idea: The hopelessly inadequate formalist theory is, to some extent, the result of considering only the propositions of mathematics and neglecting the analysis of its concepts.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], §1)
     A reaction: You'll have to read Ramsey to see how this thought pans out, but it at least gives a pointer to how to go about addressing the question.
10. Modality / B. Possibility / 1. Possibility
The concept of possibility is prior to that of necessity [Bonjour]
     Full Idea: While necessity and possibility are interdefinable concepts, it is the idea of a possible world or situation which is intuitively primary.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §1.3)
11. Knowledge Aims / A. Knowledge / 4. Belief / d. Cause of beliefs
I just confront the evidence, and let it act on me [Ramsey]
     Full Idea: I can but put the evidence before me, and let it act on my mind.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], p.202), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 70 'Deg'
     A reaction: Potter calls this observation 'downbeat', but I am an enthusiastic fan. It is roughly my view of both concept formation and of knowledge. You soak up the world, and respond appropriately. The trick is in the selection of evidence to confront.
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Our rules of thought can only be judged by pure rational insight [Bonjour]
     Full Idea: Criteria or rules do not somehow apply to themselves. They must be judged by the sort of rational insight or intuition that the rationalist is advocating.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §5.2)
Moderate rationalists believe in fallible a priori justification [Bonjour]
     Full Idea: Moderate rationalism preserves a priori justification, but rejects the idea that it is infallible.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §4.1)
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / d. Rational foundations
A priori justification can vary in degree [Bonjour]
     Full Idea: A priori justification can vary in degree.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §4.5)
     A reaction: This idea, which I trace back at least to Russell, seems to me one of breakthrough ideas in modern thought. It means that a priori knowledge can be reconnected with a posteriori knowledge.
A priori justification requires understanding but no experience [Bonjour]
     Full Idea: A proposition will count as being justified a priori as long as no appeal to experience is needed for the proposition to be justified - once it is understood.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §1.2)
     A reaction: Could you 'understand' that a square cannot be circular without appeal to experience? I'm losing faith in the pure a priori.
You can't explain away a priori justification as analyticity, and you can't totally give it up [Bonjour]
     Full Idea: Moderate empiricists try unsuccessfully to explain a priori justification by means of analyticity, and radical empiricist attempts to dispense with a priori justification end in nearly total scepticism.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §4.1)
     A reaction: My working theory is neither of the above. Because we can abstract from the physical world, we can directly see/experience generalised (and even necessary) truths about it.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
The induction problem blocks any attempted proof of physical statements [Bonjour]
     Full Idea: The attempt to prove physical statements on the basis of sensory evidence is defeated by the problem of induction.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §3.6)
     A reaction: This sounds like a logician's use of the word 'prove', which would be a pretty forlorn hope. Insofar as experience proves anything, fully sensing a chair proves its existence.
13. Knowledge Criteria / C. External Justification / 1. External Justification
Externalist theories of justification don't require believers to have reasons for their beliefs [Bonjour]
     Full Idea: An externalist theory of epistemic justification or warrant need not involve the possession by the believer of anything like a reason for thinking that their belief is true.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §3.7)
     A reaction: That is the problem with externalism. If the believer does not have a reason, then why would they believe? Externalists are interesting on justification, but daft about belief. Why do I believe I know something, when I can't recall how I learnt it?
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / a. Reliable knowledge
A belief is knowledge if it is true, certain and obtained by a reliable process [Ramsey]
     Full Idea: I have always said that a belief was knowledge if it was 1) true, ii) certain, iii) obtained by a reliable process.
     From: Frank P. Ramsey (The Foundations of Mathematics [1925], p.258), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 66 'Rel'
     A reaction: Not sure why it has to be 'certain' as well as 'true'. It seems that 'true' is objective, and 'certain' subjective. I think I know lots of things of which I am not fully certain. Reliabilism long preceded Alvin Goldman.
13. Knowledge Criteria / C. External Justification / 10. Anti External Justification
Externalism means we have no reason to believe, which is strong scepticism [Bonjour]
     Full Idea: If externalism is the final story, we have no reason to think that any of our beliefs are true, which amounts to a very strong and intuitively implausible version of scepticism.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §3.7)
     A reaction: A very good point. I may, like a cat, know many things, with good external support, but as soon as I ask sceptical questions, I sink without trace if I lack internal reasons.
14. Science / C. Induction / 2. Aims of Induction
Induction must go beyond the evidence, in order to explain why the evidence occurred [Bonjour]
     Full Idea: Inductive explanations must be conceived of as something stronger than mere Humean constant conjunction; …anything less than this will not explain why the inductive evidence occurred in the first place.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §7.7)
18. Thought / C. Content / 1. Content
All thought represents either properties or indexicals [Bonjour]
     Full Idea: I assume that the contents of thought can be accounted for by appeal to just two general sorts of ingredient - properties (including relations) and indexicals.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §6.7)
     A reaction: I don't accept that relations are a type of properties. Since he does not include objects or substances, I take it that he considers objects to be bundles of properties.
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
Indeterminacy of translation is actually indeterminacy of meaning and belief [Bonjour]
     Full Idea: The thesis of the indeterminacy of translation would be better described as the thesis of the indeterminacy of meaning and belief.
     From: Laurence Bonjour (In Defence of Pure Reason [1998], §3.5)
     A reaction: Not necessarily. It is not incoherent to believe that the target people have a coherent and stable system of meaning and belief, but finding its translation indeterminate because it is holistic, and rooted in a way of life.
27. Natural Reality / E. Cosmology / 1. Cosmology
Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG]
     Full Idea: The four major disputes in classical cosmology were whether the cosmos is 'open' or 'closed', whether it is explained mechanistically or teleologically, whether it is alive or mere matter, and whether or not it has a beginning.
     From: report of T.M. Robinson (Classical Cosmology (frags) [1997]) by PG - Db (ideas)
     A reaction: A nice summary. The standard modern view is closed, mechanistic, inanimate and non-eternal. But philosophers can ask deeper questions than physicists, and I say we are entitled to speculate when the evidence runs out.