Combining Texts

All the ideas for 'Logical Consequence', 'The Scope and Language of Science' and 'The Elements of Law'

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20 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / b. Seventeenth century philosophy
Hobbes created English-language philosophy [Hobbes, by Tuck]
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 / 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 / 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]
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]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Maths can be reduced to logic and set theory [Quine]
8. Modes of Existence / B. Properties / 1. Nature of Properties
The category of objects incorporates the old distinction of substances and their modes [Quine]
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
The qualities of the world are mere appearances; reality is the motions which cause them [Hobbes]
12. Knowledge Sources / D. Empiricism / 1. Empiricism
Experience can't prove universal truths [Hobbes]
Evidence is conception, which is imagination, which proceeds from the senses [Hobbes]
17. Mind and Body / E. Mind as Physical / 6. Conceptual Dualism
A hallucination can, like an ague, be identified with its host; the ontology is physical, the idiom mental [Quine]
20. Action / C. Motives for Action / 1. Acting on Desires
It is an error that reason should control the passions, which give right guidance on their own [Hobbes, by Tuck]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
Good and evil are what please us; goodness and badness the powers causing them [Hobbes]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
Self-preservation is basic, and people judge differently about that, implying ethical relativism [Hobbes, by Tuck]
22. Metaethics / C. The Good / 1. Goodness / c. Right and good
Hobbes shifted from talk of 'the good' to talk of 'rights' [Hobbes, by Tuck]
28. God / C. Attitudes to God / 4. God Reflects Humanity
The attributes of God just show our inability to conceive his nature [Hobbes]