Combining Texts

All the ideas for 'Higher-Order Logic', 'Externalist Theories of Empirical Knowledge' and 'Logic and Epistemology of Causal Relations'

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26 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Some say that second-order logic is mathematics, not logic [Shapiro]
If the aim of logic is to codify inferences, second-order logic is useless [Shapiro]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Second-order variables also range over properties, sets, relations or functions [Shapiro]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro]
The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / e. The Lottery paradox
The Lottery Paradox says each ticket is likely to lose, so there probably won't be a winner [Bonjour, by PG]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
8. Modes of Existence / B. Properties / 11. Properties as Sets
Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
10. Modality / B. Possibility / 1. Possibility
What is true used to be possible, but it may no longer be so [Wright,GHv]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
Externalist theories of knowledge are one species of foundationalism [Bonjour]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
The big problem for foundationalism is to explain how basic beliefs are possible [Bonjour]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / e. Pro-foundations
The main argument for foundationalism is that all other theories involve a regress leading to scepticism [Bonjour]
13. Knowledge Criteria / C. External Justification / 1. External Justification
Extreme externalism says no more justification is required than the truth of the belief [Bonjour]
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / b. Anti-reliabilism
External reliability is not enough, if the internal state of the believer is known to be irrational [Bonjour]
13. Knowledge Criteria / C. External Justification / 10. Anti External Justification
Even if there is no obvious irrationality, it may be irrational to base knowledge entirely on external criteria [Bonjour]
26. Natural Theory / C. Causation / 5. Direction of causation
p is a cause and q an effect (not vice versa) if manipulations of p change q [Wright,GHv]
We can imagine controlling floods by controlling rain, but not vice versa [Wright,GHv]
26. Natural Theory / C. Causation / 8. Particular Causation / a. Observation of causation
The very notion of a cause depends on agency and action [Wright,GHv]
We give regularities a causal character by subjecting them to experiment [Wright,GHv]
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
We must further analyse conditions for causation, into quantifiers or modal concepts [Wright,GHv]
26. Natural Theory / D. Laws of Nature / 2. Types of Laws
Some laws are causal (Ohm's Law), but others are conceptual principles (conservation of energy) [Wright,GHv]