Combining Texts

All the ideas for 'fragments/reports', 'The Very Idea of a Conceptual Scheme' and 'Frege versus Cantor and Dedekind'

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13 ideas

1. Philosophy / F. Analytic Philosophy / 7. Limitations of Analysis
Analytic philosophy focuses too much on forms of expression, instead of what is actually said [Tait]
     Full Idea: The tendency to attack forms of expression rather than attempting to appreciate what is actually being said is one of the more unfortunate habits that analytic philosophy inherited from Frege.
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], IV)
     A reaction: The key to this, I say, is to acknowledge the existence of propositions (in brains). For example, this belief will make teachers more sympathetic to pupils who are struggling to express an idea, and verbal nit-picking becomes totally irrelevant.
3. Truth / B. Truthmakers / 12. Rejecting Truthmakers
Saying truths fit experience adds nothing to truth; nothing makes sentences true [Davidson]
     Full Idea: The notion of fitting the totality of experience ...adds nothing intelligible to the simple concept of being true. ....Nothing, ...no thing, makes sentences and theories true: not experience, not surface irritations, not the world.
     From: Donald Davidson (The Very Idea of a Conceptual Scheme [1974], p.11), quoted by Willard Quine - On the Very Idea of a Third Dogma p.39
     A reaction: If you don't have a concept of what normally makes a sentence true, I don't see how you go about distinguishing what is true from what is false. You can't just examine the sentence to see if it has the 'primitive' property of truth. Holism is involved....
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The null set was doubted, because numbering seemed to require 'units' [Tait]
     Full Idea: The conception that what can be numbered is some object (including flocks of sheep) relative to a partition - a choice of unit - survived even in the late nineteenth century in the form of the rejection of the null set (and difficulties with unit sets).
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], IX)
     A reaction: This old view can't be entirely wrong! Frege makes the point that if asked to count a pack of cards, you must decide whether to count cards, or suits, or pips. You may not need a 'unit', but you need a concept. 'Units' name concept-extensions nicely!
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
We can have a series with identical members [Tait]
     Full Idea: Why can't we have a series (as opposed to a linearly ordered set) all of whose members are identical, such as (a, a, a...,a)?
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], VII)
     A reaction: The question is whether the items order themselves, which presumably the natural numbers are supposed to do, or whether we impose the order (and length) of the series. What decides how many a's there are? Do we order, or does nature?
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Without the dualism of scheme and content, not much is left of empiricism [Davidson]
     Full Idea: The third dogma of empiricism is the dualism of scheme and content, of organizing system and something waiting to be organized, which cannot be made intelligible and defensible. If we give it up, it is not clear that any distinctive empiricism remains.
     From: Donald Davidson (The Very Idea of a Conceptual Scheme [1974], p.189)
     A reaction: The first two dogmas were 'analyticity' and 'reductionism', as identified by Quine in 1953. Presumably Hume's Principles of Association (Idea 2189) would be an example of a scheme. A key issue is whether there is any 'pure' content.
13. Knowledge Criteria / E. Relativism / 6. Relativism Critique
Different points of view make sense, but they must be plotted on a common background [Davidson]
     Full Idea: Different points of view make sense, but only if there is a common co-ordinate system on which to plot them.
     From: Donald Davidson (The Very Idea of a Conceptual Scheme [1974], p.184)
     A reaction: This seems right to me. I am very struck by the close similarities between people from wildly differing cultural backgrounds, as seen, for example, at the Olympic Games.
18. Thought / E. Abstraction / 2. Abstracta by Selection
Abstraction is 'logical' if the sense and truth of the abstraction depend on the concrete [Tait]
     Full Idea: If the sense of a proposition about the abstract domain is given in terms of the corresponding proposition about the (relatively) concrete domain, ..and the truth of the former is founded upon the truth of the latter, then this is 'logical abstraction'.
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], V)
     A reaction: The 'relatively' in parentheses allows us to apply his idea to levels of abstraction, and not just to the simple jump up from the concrete. I think Tait's proposal is excellent, rather than purloining 'abstraction' for an internal concept within logic.
Cantor and Dedekind use abstraction to fix grammar and objects, not to carry out proofs [Tait]
     Full Idea: Although (in Cantor and Dedekind) abstraction does not (as has often been observed) play any role in their proofs, but it does play a role, in that it fixes the grammar, the domain of meaningful propositions, and so determining the objects in the proofs.
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], V)
     A reaction: [compressed] This is part of a defence of abstractionism in Cantor and Dedekind (see K.Fine also on the subject). To know the members of a set, or size of a domain, you need to know the process or function which created the set.
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Abstraction may concern the individuation of the set itself, not its elements [Tait]
     Full Idea: A different reading of abstraction is that it concerns, not the individuating properties of the elements relative to one another, but rather the individuating properties of the set itself, for example the concept of what is its extension.
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], VIII)
     A reaction: If the set was 'objects in the room next door', we would not be able to abstract from the objects, but we might get to the idea of things being contain in things, or the concept of an object, or a room. Wrong. That's because they are objects... Hm.
18. Thought / E. Abstraction / 8. Abstractionism Critique
Why should abstraction from two equipollent sets lead to the same set of 'pure units'? [Tait]
     Full Idea: Why should abstraction from two equipollent sets lead to the same set of 'pure units'?
     From: William W. Tait (Frege versus Cantor and Dedekind [1996])
     A reaction: [Tait is criticising Cantor] This expresses rather better than Frege or Dummett the central problem with the abstractionist view of how numbers are derived from matching groups of objects.
If abstraction produces power sets, their identity should imply identity of the originals [Tait]
     Full Idea: If the power |A| is obtained by abstraction from set A, then if A is equipollent to set B, then |A| = |B|. But this does not imply that A = B. So |A| cannot just be A, taken in abstraction, unless that can identify distinct sets, ..or create new objects.
     From: William W. Tait (Frege versus Cantor and Dedekind [1996], V)
     A reaction: An elegant piece of argument, which shows rather crucial facts about abstraction. We are then obliged to ask how abstraction can create an object or a set, if the central activity of abstraction is just ignoring certain features.
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
Criteria of translation give us the identity of conceptual schemes [Davidson]
     Full Idea: Studying the criteria of translation is a way of focusing on criteria of identity for conceptual schemes.
     From: Donald Davidson (The Very Idea of a Conceptual Scheme [1974], p.184)
     A reaction: This is why it was an inspired idea of Quine's to make translation a central topic in philosophy. We must be cautious, though, about saying that the language is the conceptual scheme, as that leaves animals with no scheme at all.
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]
     Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice.
     From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where?