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All the ideas for 'The Really Hard Problem', 'First-Order Logic' and 'works'

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16 ideas

1. Philosophy / G. Scientific Philosophy / 3. Scientism
Philosophy is not separate from or above empirical science [Neurath]
     Full Idea: There is no such thing as philosophy as a basic or universal science alongside or above the various fields of the one empirical science.
     From: Otto Neurath (works [1930]), quoted by Simon Critchley - Continental Philosophy - V. Short Intro Ch.6
     A reaction: This is what you get for becoming an empiricist. If philosophy is the quest for human wisdom, it seems to me highly unlikely that physical sciences will provide it. Human interests and values and understanding play absolutely no role in physics.
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W]
     Full Idea: A logic is a collection of closely related artificial languages, and its older meaning is the study of the rules of sound argument. The languages can be used as a framework for studying rules of argument.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.1)
     A reaction: [Hodges then says he will stick to the languages] The suspicion is that one might confine the subject to the artificial languages simply because it is easier, and avoids the tricky philosophical questions. That approximates to computer programming.
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
     Full Idea: To have a truth-value, a first-order formula needs an 'interpretation' (I) of its constants, and a 'valuation' (ν) of its variables. Something in the world is attached to the constants; objects are attached to variables.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.3)
There are three different standard presentations of semantics [Hodges,W]
     Full Idea: Semantic rules can be presented in 'Tarski style', where the interpretation-plus-valuation is reduced to the same question for simpler formulas, or the 'Henkin-Hintikka style' in terms of games, or the 'Barwise-Etchemendy style' for computers.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.3)
     A reaction: I haven't yet got the hang of the latter two, but I note them to map the territory.
I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
     Full Idea: I |= φ means that the formula φ is true in the interpretation I.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.5)
     A reaction: [There should be no space between the vertical and the two horizontals!] This contrasts with |-, which means 'is proved in'. That is a syntactic or proof-theoretic symbol, whereas |= is a semantic symbol (involving truth).
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
     Full Idea: Downward Löwenheim-Skolem (the weakest form): If L is a first-order language with at most countably many formulas, and T is a consistent theory in L. Then T has a model with at most countably many elements.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.10)
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
     Full Idea: Upward Löwenheim-Skolem: every first-order theory with infinite models has arbitrarily large models.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.10)
5. Theory of Logic / K. Features of Logics / 6. Compactness
If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
     Full Idea: Compactness Theorem: suppose T is a first-order theory, ψ is a first-order sentence, and T entails ψ. Then there is a finite subset U of T such that U entails ψ.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.10)
     A reaction: If entailment is possible, it can be done finitely.
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
A 'set' is a mathematically well-behaved class [Hodges,W]
     Full Idea: A 'set' is a mathematically well-behaved class.
     From: Wilfrid Hodges (First-Order Logic [2001], 1.6)
15. Nature of Minds / B. Features of Minds / 2. Unconscious Mind
Research suggest that we overrate conscious experience [Flanagan]
     Full Idea: The emerging consensus is that we probably overrate the power of conscious experience in our lives. Freud, of course, said the same thing for different reasons.
     From: Owen Flanagan (The Really Hard Problem [2007], 3 'Ontology')
     A reaction: [He cites Pockett, Banks and Gallagher 2006]. Freud was concerned with big deep secrets, but the modern view concerns ordinary decisions and perceptions. An important idea, which should incline us all to become Nietzscheans.
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
Sensations may be identical to brain events, but complex mental events don't seem to be [Flanagan]
     Full Idea: There is still some hope for something like identity theory for sensations. But almost no one believes that strict identity theory will work for more complex mental states. Strict identity is stronger than type neurophysicalism.
     From: Owen Flanagan (The Really Hard Problem [2007], 3 'Ontology')
     A reaction: It is so hard to express the problem. What needs to be explained? How can one bunch of neurons represent many different things? It's not like computing. That just transfers the data to brains, where the puzzling stuff happens.
22. Metaethics / B. Value / 1. Nature of Value / b. Fact and value
Morality is normative because it identifies best practices among the normal practices [Flanagan]
     Full Idea: Morality is 'normative' in the sense that it consists of the extraction of ''good' or 'excellent' practices from common practices.
     From: Owen Flanagan (The Really Hard Problem [2007], 4 'Naturalism')
22. Metaethics / B. Value / 2. Values / f. Altruism
For Darwinians, altruism is either contracts or genetics [Flanagan]
     Full Idea: Two explanations came forward in the neo-Darwinian synthesis. Altruism is either 1) person-based reciprocal altruism, or 2) gene-based kin altruism.
     From: Owen Flanagan (The Really Hard Problem [2007], 2 'Darwin')
     A reaction: Flanagan obviously thinks there is also 'genuine psychological atruism'. Presumably we don't explain mathematics or music or the desire to travel as either contracts or genetics, so we have other explanations available.
22. Metaethics / C. The Good / 2. Happiness / b. Eudaimonia
We need Eudaimonics - the empirical study of how we should flourish [Flanagan]
     Full Idea: It would be nice if I could advance the case for Eudaimonics - empirical enquiry into the nature, causes, and constituents of flourishing, …and the case for some ways of living and being as better than others.
     From: Owen Flanagan (The Really Hard Problem [2007], 4 'Normative')
     A reaction: Things seem to be moving in that direction. Lots of statistics about happiness have been appearing.
24. Political Theory / D. Ideologies / 9. Communism
Alienation is not finding what one wants, or being unable to achieve it [Flanagan]
     Full Idea: What Marx called 'alienation' is the widespread condition of not being able to discover what one wants, or not being remotely positioned to achieve.
     From: Owen Flanagan (The Really Hard Problem [2007], 2 'Expanding')
     A reaction: I took alienation to concern people's relationship to the means of production in their trade. On Flanagan's definition I would expect almost everyone aged under 20 to count as alienated.
29. Religion / C. Spiritual Disciplines / 3. Buddhism
Buddhists reject God and the self, and accept suffering as key, and liberation through wisdom [Flanagan]
     Full Idea: Buddhism rejected the idea of a creator God, and the unchanging self [atman]. They accept the appearance-reality distinction, reward for virtue [karma], suffering defining our predicament, and that liberation [nirvana] is possible through wisdom.
     From: Owen Flanagan (The Really Hard Problem [2007], 3 'Buddhism')
     A reaction: [Compressed] Flanagan is an analytic philosopher and a practising Buddhist. Looking at a happiness map today which shows Europeans largely happy, and Africans largely miserable, I can see why they thought suffering was basic.