Combining Texts

All the ideas for 'Mahaprajnaparamitashastra', 'The philosophical basis of intuitionist logic' and 'Vagueness: a global approach'

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16 ideas

4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Dummett says classical logic rests on meaning as truth, while intuitionist logic rests on assertability [Dummett, by Kitcher]
     Full Idea: Dummett argues that classical logic depends on the choice of the concept of truth as central to the theory of meaning, while for the intuitionist the concept of assertability occupies this position.
     From: report of Michael Dummett (The philosophical basis of intuitionist logic [1973]) by Philip Kitcher - The Nature of Mathematical Knowledge 06.5
     A reaction: Since I can assert any nonsense I choose, this presumably means 'warranted' assertability, which is tied to the concept of proof in mathematics. You can reason about falsehoods, or about uninterpreted variables. Can you 'assert' 'Fx'?
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Indeterminacy is in conflict with classical logic [Fine,K]
     Full Idea: I now believe that the existence of indeterminacy is in conflict with classical logic.
     From: Kit Fine (Vagueness: a global approach [2020], 3)
     A reaction: I think that prior to this Fine had defended classical logic. Presumably the difficulty is over Bivalence. Nietzsche spotted this problem, despite not being a logician. Logic has to simplify the world. Hence philosophy is quite different from logic.
5. Theory of Logic / G. Quantification / 1. Quantification
Classical quantification is an infinite conjunction or disjunction - but you may not know all the instances [Dummett]
     Full Idea: Classical quantification represents an infinite conjunction or disjunction, and the truth-value is determined by the infinite sum or product of the instances ....but this presupposes that all the instances already possess determinate truth-values.
     From: Michael Dummett (The philosophical basis of intuitionist logic [1973], p.246)
     A reaction: In the case of the universal quantifier, Dummett is doing no more than citing the classic empiricism objection to induction - that you can't make the universal claim if you don't know all the instances. The claim is still meaningful, though.
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
Classical semantics has referents for names, extensions for predicates, and T or F for sentences [Fine,K]
     Full Idea: A precise language is often assigned a classical semantics, in which the semantic value of a name is its referent, the semantic value of a predicate is its extension (the objects of which it is true), and the value of a sentence is True or False.
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: Helpful to have this clear statement of how predicates are treated. This extensionalism in logic causes trouble when it creeps into philosophy, and people say that 'red' just means all the red things. No it doesn't.
7. Existence / D. Theories of Reality / 10. Vagueness / a. Problem of vagueness
Local indeterminacy concerns a single object, and global indeterminacy covers a range [Fine,K]
     Full Idea: Vagueness concerns 'local' indeterminacy, such as whether one man in the lineup is bald, and 'global' indeterminacy, applying to a range of cases, as when it is indeterminate how 'bald' applies to the lineup. But how do these relate?
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: This puts the focus either on objects or on predicates which are vague.
Conjoining two indefinites by related sentences seems to produce a contradiction [Fine,K]
     Full Idea: If 'P is red' and 'P is orange' are indefinite, then 'P is red and P is orange' seems false, because red and orange are exclusive. But if two conjoined indefinite sentences are false, that makes 'P is red and P is red' false, when it should be indefinite.
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: [compressed] This is the problem of 'penumbral connection', where two indefinite values are still logically related, by excluding one another. Presumably 'P is red and P is of indefinite shape' can be true? Doubtful about this argument.
Standardly vagueness involves borderline cases, and a higher standpoint from which they can be seen [Fine,K]
     Full Idea: Standard notions of vagueness all accept borderline cases, and presuppose a higher standpoint from which a judgement of being borderline F, rather than simply being F or being not F, can be made.
     From: Kit Fine (Vagueness: a global approach [2020], 3)
     A reaction: He says that the concept of borderline cases is an impediment to understanding vagueness. Proposing a third group when you are struggling to separate two other groups doesn't seem helpful, come to think of it. Limbo cases.
7. Existence / D. Theories of Reality / 10. Vagueness / c. Vagueness as ignorance
Identifying vagueness with ignorance is the common mistake of confusing symptoms with cause [Fine,K]
     Full Idea: We can see Epistemicism [vagueness as ignorance] as a common and misguided tendency to identify a cause with its symptoms. We are unsure how to characterise vagueness, and identify it with the resulting ignorance, instead of explaining it.
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: Love it. This echoes my repeated plea in these reactions to stop identifying features of reality with the functions which embody them or the patterns they create. We need to explain them, and must dig deeper.
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
Supervaluation can give no answer to 'who is the last bald man' [Fine,K]
     Full Idea: Under supervaluation there should always be someone who is the last bald man in the sequence, but there is always an acceptable way to make some other man the last bald man.
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: Fine seems to take this as a conclusive refutation of the supervaluation approach. Fine says (p.41) that supervaluation says there is a precisification for every instance.
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
We do not have an intelligible concept of a borderline case [Fine,K]
     Full Idea: We simply have no intelligible notion of local indeterminacy or of a borderline case.
     From: Kit Fine (Vagueness: a global approach [2020], 2)
     A reaction: He mentions cases which are near a borderline, and cases which are hard to decide, but denies that these are intrinsically borderline. If there are borderline cases between red and orange, what are the outer boundaries of the border?
16. Persons / D. Continuity of the Self / 2. Mental Continuity / b. Self as mental continuity
It seems absurd that there is no identity of any kind between two objects which involve survival [Fine,K]
     Full Idea: Pace Parfit and others, it boggles the mind that survival could be independent of any relation of identity between the currently existing object and the objects that subsequently exist.
     From: Kit Fine (Vagueness: a global approach [2020], 3)
     A reaction: Yes. If the self or mind just consists of a diachronic trail of memories such that the two ends of the trail have no connection at all, that isn't the kind of survival that any of us want. I want to live my life, not a life.
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Stating a sentence's truth-conditions is just paraphrasing the sentence [Dummett]
     Full Idea: An ability to state the condition for the truth of a sentence is, in effect, no more than an ability to express the content of the sentence in other words.
     From: Michael Dummett (The philosophical basis of intuitionist logic [1973], p.224)
     A reaction: Alternatively, if you give something other than a paraphrase of the sentence as its meaning (such as a proof of its truth), then you seem to have departed from your target sentence. Can we reduce and eliminate our sentences in this way?
If a sentence is effectively undecidable, we can never know its truth conditions [Dummett]
     Full Idea: If a sentence is effectively undecidable, the condition which must obtain for it to be true is not one which we are capable of recognising whenever it obtains, or of getting ourselves in a position to do so.
     From: Michael Dummett (The philosophical basis of intuitionist logic [1973], p.225)
     A reaction: The instances of 'undecidable' sentences are most clearly seen in mathematics, such as the Continuum Hypothesis or Goldbach's Conjecture, or anything involving vast infinite cardinals. But do you need precise truth-conditions for meaning?
19. Language / A. Nature of Meaning / 6. Meaning as Use
Meaning as use puts use beyond criticism, and needs a holistic view of language [Dummett]
     Full Idea: If use constitutes meaning, it might seem that use is beyond criticism. ....But such an attitude can, ultimately, be supported onlly by the adoption of a holistic view of language.
     From: Michael Dummett (The philosophical basis of intuitionist logic [1973], p.218)
     A reaction: Dummett goes on to say that the rejection of the holistic view of mathematical meaning leads to his preference for intuitionistic logic.
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]
     Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom.
     From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88)
     A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate').
26. Natural Theory / D. Laws of Nature / 4. Regularities / a. Regularity theory
We identify laws with regularities because we mistakenly identify causes with their symptoms [Fine,K]
     Full Idea: There is a common tendency to identify a cause with its symptoms. Hence we are not sure how to characterise a law, and so we identify it with the regularities to which it gives rise.
     From: Kit Fine (Vagueness: a global approach [2020], 1)
     A reaction: A lovely clear identification of my pet hate, which is superficial accounts of things, which claim to be the last word, but actually explain nothing.