Combining Texts

All the ideas for 'poems', 'Beyond internal Foundations to external Virtues' and 'Must We Believe in Set Theory?'

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21 ideas

2. Reason / A. Nature of Reason / 6. Coherence
We can't attain a coherent system by lopping off any beliefs that won't fit [Sosa]
     Full Idea: Coherence involves the logical, explanatory and probabilistic relations among one's beliefs, but it could not do to attain a tightly iterrelated system by lopping off whatever beliefs refuse to fit.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.4)
     A reaction: This is clearly right, so the coherentist has to distinguish between lopping off a belief because it is inconvenient (fundamentalists rejecting textual contradictions), and lopping it off because it is wrong (chemists rejecting phlogiston).
4. Formal Logic / F. Set Theory ST / 1. Set Theory
The logic of ZF is classical first-order predicate logic with identity [Boolos]
     Full Idea: The logic of ZF Set Theory is classical first-order predicate logic with identity.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.121)
     A reaction: This logic seems to be unable to deal with very large cardinals, precisely those that are implied by set theory, so there is some sort of major problem hovering here. Boolos is fairly neutral.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
A few axioms of set theory 'force themselves on us', but most of them don't [Boolos]
     Full Idea: Maybe the axioms of extensionality and the pair set axiom 'force themselves on us' (Gödel's phrase), but I am not convinced about the axioms of infinity, union, power or replacement.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.130)
     A reaction: Boolos is perfectly happy with basic set theory, but rather dubious when very large cardinals come into the picture.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos]
     Full Idea: The naïve view of set theory (that any zero or more things form a set) is natural, but inconsistent: the things that do not belong to themselves are some things that do not form a set.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.127)
     A reaction: As clear a summary of Russell's Paradox as you could ever hope for.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos]
     Full Idea: According to the iterative conception, every set is formed at some stage. There is a relation among stages, 'earlier than', which is transitive. A set is formed at a stage if and only if its members are all formed before that stage.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.126)
     A reaction: He gives examples of the early stages, and says the conception is supposed to 'justify' Zermelo set theory. It is also supposed to make the axioms 'natural', rather than just being selected for convenience. And it is consistent.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Infinite natural numbers is as obvious as infinite sentences in English [Boolos]
     Full Idea: The existence of infinitely many natural numbers seems to me no more troubling than that of infinitely many computer programs or sentences of English. There is, for example, no longest sentence, since any number of 'very's can be inserted.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.129)
     A reaction: If you really resisted an infinity of natural numbers, presumably you would also resist an actual infinity of 'very's. The fact that it is unclear what could ever stop a process doesn't guarantee that the process is actually endless.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
Mathematics and science do not require very high orders of infinity [Boolos]
     Full Idea: To the best of my knowledge nothing in mathematics or science requires the existence of very high orders of infinity.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.122)
     A reaction: He is referring to particular high orders of infinity implied by set theory. Personally I want to wield Ockham's Razor. Is being implied by set theory a sufficient reason to accept such outrageous entities into our ontology?
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
Mathematics isn't surprising, given that we experience many objects as abstract [Boolos]
     Full Idea: It is no surprise that we should be able to reason mathematically about many of the things we experience, for they are already 'abstract'.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.129)
     A reaction: He has just given a list of exemplary abstract objects (Idea 10489), but I think there is a more interesting idea here - that our experience of actual physical objects is to some extent abstract, as soon as it is conceptualised.
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
The phenomenal concept of an eleven-dot pattern does not include the concept of eleven [Sosa]
     Full Idea: You could detect the absence of an eleven-dot pattern without having counted the dots, so your phenomenal concept of that array is not an arithmetical concept, and its content will not yield that its dots do indeed number eleven.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 7.3)
     A reaction: Sosa is discussing foundational epistemology, but this draws attention to the gulf that has to be leaped by structuralists. If eleven is not derived from the pattern, where does it come from? Presumably two eleven-dotters are needed, to map them.
8. Modes of Existence / D. Universals / 1. Universals
It is lunacy to think we only see ink-marks, and not word-types [Boolos]
     Full Idea: It's a kind of lunacy to think that sound scientific philosophy demands that we think that we see ink-tracks but not words, i.e. word-types.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.128)
     A reaction: This seems to link him with Armstrong's mockery of 'ostrich nominalism'. There seems to be some ambiguity with the word 'see' in this disagreement. When we look at very ancient scratches on stones, why don't we always 'see' if it is words?
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
I am a fan of abstract objects, and confident of their existence [Boolos]
     Full Idea: I am rather a fan of abstract objects, and confident of their existence. Smaller numbers, sets and functions don't offend my sense of reality.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.128)
     A reaction: The great Boolos is rather hard to disagree with, but I disagree. Logicians love abstract objects, indeed they would almost be out of a job without them. It seems to me they smuggle them into our ontology by redefining either 'object' or 'exists'.
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos]
     Full Idea: We twentieth century city dwellers deal with abstract objects all the time, such as bank balances, radio programs, software, newspaper articles, poems, mistakes, triangles.
     From: George Boolos (Must We Believe in Set Theory? [1997], p.129)
     A reaction: I find this claim to be totally question-begging, and typical of a logician. The word 'object' gets horribly stretched in these discussions. We can create concepts which have all the logical properties of objects. Maybe they just 'subsist'?
11. Knowledge Aims / A. Knowledge / 1. Knowledge
It is acceptable to say a supermarket door 'knows' someone is approaching [Sosa]
     Full Idea: I am quite flexible on epistemic terminology, and am even willing to grant that a supermarket door can 'know' that someone is approaching.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.6)
     A reaction: I take this amazing admission to be a hallmark of externalism. Sosa must extend this to thermostats. So flowers know the sun has come out. This is knowledge without belief. Could the door ever be 'wrong'?
12. Knowledge Sources / C. Rationalism / 1. Rationalism
In reducing arithmetic to self-evident logic, logicism is in sympathy with rationalism [Sosa]
     Full Idea: In trying to reduce arithmetic to self-evident logical axioms, logicism is in sympathy with rationalism.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.7)
     A reaction: I have heard Frege called "the greatest of all rationalist philosophers". However, the apparent reduction of arithmetic to analytic truths played into the hands of logical positivists, who could then marginalise arithmetic.
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Most of our knowledge has insufficient sensory support [Sosa]
     Full Idea: Almost nothing that one knows of history or geography or science has adequate sensory support, present or even recalled.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.7)
     A reaction: This seems a bit glib, and may be false. The main issue to which this refers is, of course, induction, which (almost by definition) is a supposedly empirical process which goes beyond the empirical evidence.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / c. Empirical foundations
Perception may involve thin indexical concepts, or thicker perceptual concepts [Sosa]
     Full Idea: There is a difference between having just an indexical concept which one can apply to a perceptual characteristic (just saying 'this is thus'), and having a thicker perceptual concept of that characteristic.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 7.2)
     A reaction: Both of these, of course, would precede any categorial concepts that enabled one to identify the characteristic or the object. This is a ladder foundationalists must climb if they are to reach the cellar of basic beliefs.
Do beliefs only become foundationally justified if we fully attend to features of our experience? [Sosa]
     Full Idea: Are foundationally justified beliefs perhaps those that result from attending to our experience and to features of it or in it?
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 7.3)
     A reaction: A promising suggestion. I do think our ideas acquire a different epistmological status once we have given them our full attention, though is that merely full consciousness, or full thoughtful evaluation? The latter I take to be what matters. Cf Idea 2414.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / d. Rational foundations
Some features of a thought are known directly, but others must be inferred [Sosa]
     Full Idea: Some intrinsic features of our thoughts are attributable to them directly, or foundationally, while others are attributable only based on counting or inference.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 7.5)
     A reaction: In practice the brain combines the two at a speed which makes the distinction impossible. I'll show you ten dot-patterns: you pick out the sixer. The foundationalist problem is that only those drained of meaning could be foundational.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / e. Pro-foundations
Much propositional knowledge cannot be formulated, as in recognising a face [Sosa]
     Full Idea: Much of our propositional knowledge is not easily formulable, as when a witness looking at a police lineup may know what the culprit's face looks like.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.1)
     A reaction: This is actually a very helpful defence of foundationalism, because it shows that we will accept perceptual experiences as knowledge when they are not expressed as explicit propositions. Davidson (Idea 8801), for example, must deal with this difficulty.
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Fully comprehensive beliefs may not be knowledge [Sosa]
     Full Idea: One's beliefs can be comprehensively coherent without amounting to knowledge.
     From: Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.6)
     A reaction: Beliefs that are fully foundational or reliably sourced may also fail to be knowledge. I take it that any epistemological theory must be fallibilist (Idea 6898). Rational coherentism will clearly be sensitive to error.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
Nomos is king [Pindar]
     Full Idea: Nomos is king.
     From: Pindar (poems [c.478 BCE], S 169), quoted by Thomas Nagel - The Philosophical Culture
     A reaction: This seems to be the earliest recorded shot in the nomos-physis wars (the debate among sophists about moral relativism). It sounds as if it carries the full relativist burden - that all that matters is what has been locally decreed.