Combining Texts

All the ideas for 'Classical Cosmology (frags)', 'Thought' and 'Thinking About Logic'

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72 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Inference is never a conscious process [Harman]
2. Reason / A. Nature of Reason / 4. Aims of Reason
Reasoning might be defined in terms of its functional role, which is to produce knowledge [Harman]
2. Reason / A. Nature of Reason / 9. Limits of Reason
If you believe that some of your beliefs are false, then at least one of your beliefs IS false [Harman]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
Necessity is provability in S4, and true in all worlds in S5 [Read]
4. Formal Logic / E. Nonclassical Logics / 4. Fuzzy Logic
There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read]
4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
Same say there are positive, negative and neuter free logics [Read]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
Realisms like the full Comprehension Principle, that all good concepts determine sets [Read]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Any two states are logically linked, by being entailed by their conjunction [Harman]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Not all validity is captured in first-order logic [Read]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Deductive logic is the only logic there is [Harman]
The non-emptiness of the domain is characteristic of classical logic [Read]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Semantics must precede proof in higher-order logics, since they are incomplete [Read]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
We should exclude second-order logic, precisely because it captures arithmetic [Read]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read]
Logical consequence isn't just a matter of form; it depends on connections like round-square [Read]
5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
You don't have to accept the conclusion of a valid argument [Harman]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Our underlying predicates represent words in the language, not universal concepts [Harman]
Logical form is the part of a sentence structure which involves logical elements [Harman]
A theory of truth in a language must involve a theory of logical form [Harman]
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
A theory is logically closed, which means infinite premisses [Read]
5. Theory of Logic / G. Quantification / 1. Quantification
Quantifiers are second-order predicates [Read]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
In second-order logic the higher-order variables range over all the properties of the objects [Read]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A logical truth is the conclusion of a valid inference with no premisses [Read]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Any first-order theory of sets is inadequate [Read]
5. Theory of Logic / K. Features of Logics / 6. Compactness
Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read]
Compactness does not deny that an inference can have infinitely many premisses [Read]
Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read]
Compactness makes consequence manageable, but restricts expressive power [Read]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Self-reference paradoxes seem to arise only when falsity is involved [Read]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read]
Second-order arithmetic covers all properties, ensuring categoricity [Read]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / g. Von Neumann numbers
Von Neumann numbers are helpful, but don't correctly describe numbers [Read]
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
Would a language without vagueness be usable at all? [Read]
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
Supervaluations say there is a cut-off somewhere, but at no particular place [Read]
A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read]
Identities and the Indiscernibility of Identicals don't work with supervaluations [Read]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
A haecceity is a set of individual properties, essential to each thing [Read]
10. Modality / A. Necessity / 2. Nature of Necessity
Equating necessity with truth in every possible world is the S5 conception of necessity [Read]
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
The point of conditionals is to show that one will accept modus ponens [Read]
The standard view of conditionals is that they are truth-functional [Read]
Some people even claim that conditionals do not express propositions [Read]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read]
10. Modality / E. Possible worlds / 1. Possible Worlds / c. Possible worlds realism
How can modal Platonists know the truth of a modal proposition? [Read]
10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / c. Worlds as propositions
A possible world is a determination of the truth-values of all propositions of a domain [Read]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read]
11. Knowledge Aims / A. Knowledge / 4. Belief / e. Belief holism
You have to reaffirm all your beliefs when you make a logical inference [Harman]
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
Only lack of imagination makes us think that 'cats are animals' is analytic [Harman]
Analyticity is postulated because we can't imagine some things being true, but we may just lack imagination [Harman]
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
Memories are not just preserved, they are constantly reinferred [Harman]
13. Knowledge Criteria / A. Justification Problems / 3. Internal or External / b. Pro-externalism
People's reasons for belief are rarely conscious [Harman]
13. Knowledge Criteria / B. Internal Justification / 3. Evidentialism / a. Evidence
We don't distinguish between accepting, and accepting as evidence [Harman]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
In negative coherence theories, beliefs are prima facie justified, and don't need initial reasons [Harman, by Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
Coherence avoids scepticism, because it doesn't rely on unprovable foundations [Harman]
14. Science / C. Induction / 2. Aims of Induction
Induction is an attempt to increase the coherence of our explanations [Harman]
15. Nature of Minds / C. Capacities of Minds / 3. Abstraction by mind
The mind abstracts ways things might be, which are nonetheless real [Read]
16. Persons / C. Self-Awareness / 2. Knowing the Self
We see ourselves in the world as a map [Harman]
17. Mind and Body / B. Behaviourism / 2. Potential Behaviour
Defining dispositions is circular [Harman]
17. Mind and Body / E. Mind as Physical / 4. Connectionism
Could a cloud have a headache if its particles formed into the right pattern? [Harman]
18. Thought / B. Mechanics of Thought / 4. Language of Thought
Are there any meanings apart from in a language? [Harman]
19. Language / A. Nature of Meaning / 1. Meaning
Speech acts, communication, representation and truth form a single theory [Harman]
19. Language / A. Nature of Meaning / 8. Synonymy
There is only similarity in meaning, never sameness in meaning [Harman]
19. Language / A. Nature of Meaning / 9. Ambiguity
Ambiguity is when different underlying truth-conditional structures have the same surface form [Harman]
19. Language / C. Assigning Meanings / 4. Compositionality
Negative existentials with compositionality make the whole sentence meaningless [Read]
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
Truth in a language is explained by how the structural elements of a sentence contribute to its truth conditions [Harman]
19. Language / D. Propositions / 1. Propositions
Sentences are different from propositions, since two sentences can express one proposition [Harman]
A proposition objectifies what a sentence says, as indicative, with secure references [Read]
19. Language / E. Analyticity / 3. Analytic and Synthetic
The analytic/synthetic distinction is a silly division of thought into encyclopaedia and dictionary [Harman]
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
Many predicates totally resist translation, so a universal underlying structure to languages is unlikely [Harman]
27. Natural Reality / E. Cosmology / 1. Cosmology
Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG]