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All the ideas for 'Logical Consequence', 'Mathematical Methods in Philosophy' and 'works'

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27 ideas

4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 9. Philosophical Logic
Three stages of philosophical logic: syntactic (1905-55), possible worlds (1963-85), widening (1990-) [Horsten/Pettigrew]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 8. Material Implication
A step is a 'material consequence' if we need contents as well as form [Beall/Restall]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Logical formalization makes concepts precise, and also shows their interrelation [Horsten/Pettigrew]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Models are mathematical structures which interpret the non-logical primitives [Beall/Restall]
Models are sets with functions and relations, and truth built up from the components [Horsten/Pettigrew]
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall]
7. Existence / A. Nature of Existence / 1. Nature of Existence
If 'exist' doesn't express a property, we can hardly ask for its essence [Horsten/Pettigrew]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
A Tarskian model can be seen as a possible state of affairs [Horsten/Pettigrew]
The 'spheres model' was added to possible worlds, to cope with counterfactuals [Horsten/Pettigrew]
10. Modality / E. Possible worlds / 1. Possible Worlds / b. Impossible worlds
Epistemic logic introduced impossible worlds [Horsten/Pettigrew]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Possible worlds models contain sets of possible worlds; this is a large metaphysical commitment [Horsten/Pettigrew]
Using possible worlds for knowledge and morality may be a step too far [Horsten/Pettigrew]
14. Science / B. Scientific Theories / 3. Instrumentalism
Special relativity, unlike general relativity, was operationalist in spirit [Putnam on Einstein]
26. Natural Theory / C. Causation / 1. Causation
Einstein took causation to be the bedrock of physics [Einstein, by Coveney/Highfield]
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
General relativity assumes laws of nature are the same in all frames of reference [Einstein, by Close]
27. Natural Reality / A. Classical Physics / 1. Mechanics / d. Gravity
Newton is a special case of Einstein's general theory, with an infinite speed of light [Einstein, by Close]
27. Natural Reality / B. Modern Physics / 1. Relativity / a. Special relativity
The theory is 'special' because it sticks to observers moving straight, at constant speeds [Einstein, by Farmelo]
Assume the speed of light is constant for all observers, and the laws of physics are the same [Einstein, by Farmelo]
27. Natural Reality / B. Modern Physics / 1. Relativity / b. General relativity
General Relativity says there is no absolute force or acceleration [Einstein, by Close]
27. Natural Reality / B. Modern Physics / 4. Standard Model / d. Mass
Mass is a measure of energy content [Einstein]
27. Natural Reality / C. Space / 6. Space-Time
Space-time arises from the connection between measurements of space and of time [Einstein, by Farmelo]
28. God / C. Attitudes to God / 5. Atheism
I do not believe in a personal God [Einstein]