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All the ideas for 'Intensional Logic', 'Knowledge:Readings in Cont.Epist' and 'Time and Free Will'

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18 ideas

4. Formal Logic / E. Nonclassical Logics / 8. Intensional Logic
If terms change their designations in different states, they are functions from states to objects [Fitting]
     Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3)
     A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough.
Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting]
     Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3.3)
4. Formal Logic / E. Nonclassical Logics / 9. Awareness Logic
Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting]
     Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
     A reaction: [He cites Fagin and Halpern 1988 for this]
4. Formal Logic / E. Nonclassical Logics / 10. Justification Logics
Justication logics make explicit the reasons for mathematical truth in proofs [Fitting]
     Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Classical logic is deliberately extensional, in order to model mathematics [Fitting]
     Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics.
     From: Melvin Fitting (Intensional Logic [2007], §1)
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ-abstraction disambiguates the scope of modal operators [Fitting]
     Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □.
     From: Melvin Fitting (Intensional Logic [2007], §3.3)
     A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic.
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Definite descriptions pick out different objects in different possible worlds [Fitting]
     Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally.
     From: Melvin Fitting (Intensional Logic [2007], 3.4)
     A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others.
11. Knowledge Aims / A. Knowledge / 1. Knowledge
Perception, introspection, testimony, memory, reason, and inference can give us knowledge [Bernecker/Dretske]
     Full Idea: The basic sources of knowledge and justification are perception, introspection, testimony, memory, reason, and inference.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.V Int)
12. Knowledge Sources / B. Perception / 7. Causal Perception
Causal theory says true perceptions must be caused by the object perceived [Bernecker/Dretske]
     Full Idea: The causal theory of perceptions says that to perceive an object is to have a sense-datum caused by that object; it is not enough for the world to be the way we perceive it; the world must cause the perception.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.V Int)
     A reaction: All causal theories seem dubious to me; what causes something is not the same was what it means, or refers to, or what justifies it. The hallmark of successful perception is truth. I would perceive a tree if God planted the perception in me.
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
You can acquire new knowledge by exploring memories [Bernecker/Dretske]
     Full Idea: You can first come to know by remembering, as in learning how many windows there were in your childhood home by imagining a tour.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.V Int)
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
Justification can be of the belief, or of the person holding the belief [Bernecker/Dretske]
     Full Idea: There is a distinction between a person being justified in holding a belief, and the belief itself being justified.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.II Int)
     A reaction: This is the crucial and elementary distinction which even the most sophisticated of epistemologists keep losing sight of. Epistemology is about persons. All true beliefs are justified - by the facts!
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
Foundationalism aims to avoid an infinite regress [Bernecker/Dretske]
     Full Idea: The driving force behind foundationalism has always been the threat of an infinite regress.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.III Int)
     A reaction: You could just live with the regress (Peter Klein), or say that the regress fades away, or that it is cut off by social epistemological convention, or the regress circles round and rejoins.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Infallible sensations can't be foundations if they are non-epistemic [Bernecker/Dretske]
     Full Idea: If sense experiences are non-epistemic they may be infallible, but they are unsuitable for providing the foundations for other beliefs.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.III Int)
     A reaction: If we experience flashing lights in the retina, or an afterimage, we don't think we are seeing objects, so why is normal perception different? Ans: because it is supported by judgement.
13. Knowledge Criteria / C. External Justification / 1. External Justification
Justification is normative, so it can't be reduced to cognitive psychology [Bernecker/Dretske]
     Full Idea: The concept of justification is absolutely central to epistemology; but this concept is normative (i.e. it lays down norms), so epistemology can't be reduced to factual cognitive psychology.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.III Int)
     A reaction: A simple rejection of the 'epistemology naturalised' idea. Best to start with slugs rather than people. You can confuse a slug, so it has truth or falsehood, but what is slug normativity? This is an interesting discussion point, not an argument.
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Modern arguments against the sceptic are epistemological and semantic externalism, and the focus on relevance [Bernecker/Dretske]
     Full Idea: In modern epistemology the three strategies to rebut the sceptic are 1) epistemological externalism, 2) the 'relevant alternative account of knowledge' (that scepticism is too extreme to be relevant), and 3) semantic externalism.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.IV Int)
14. Science / C. Induction / 5. Paradoxes of Induction / a. Grue problem
Predictions are bound to be arbitrary if they depend on the language used [Bernecker/Dretske]
     Full Idea: The new riddle of induction ('grue') seems to demonstrate that sound inductive inferences are arbitrary because they depend on the actual language people use to formulate predictions.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.V Int)
17. Mind and Body / E. Mind as Physical / 5. Causal Argument
Experienced time means no two mental moments are ever alike [Bergson]
     Full Idea: If duration [experienced time] is what we say, deep-seated psychic states are radically heterogeneous to each other, and it is impossible that any two of them should be quite alike, since they are two different moments in a life-story.
     From: Henri Bergson (Time and Free Will [1889], p.220), quoted by Pete A.Y. Gunter - Bergson p.174
     A reaction: This implies that we are intrinsically unpredictable, and there certainly can't be a regularity account of mental causation. The sense of time is said to make the self radically different from the rest of reality. Bergson later rejected dualism.
18. Thought / C. Content / 6. Broad Content
Semantic externalism ties content to the world, reducing error [Bernecker/Dretske]
     Full Idea: Semantic externalism ties our mental content down to our actual environment so there is no possibility of massive error.
     From: Bernecker / Dretske (Knowledge:Readings in Cont.Epist [2000], Pt.V Int)
     A reaction: This sounds more prescriptive than descriptive. People do make massive errors in their concepts. Maybe educated people are more externalist (respectful of experts) than uneducated people?