Combining Texts

All the ideas for 'Logical Consequence', 'De Essentia' and 'Ontological Categories'

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23 ideas

4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
10688 '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
10690 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
10691 Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
10695 Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 8. Material Implication
10689 A step is a 'material consequence' if we need contents as well as form [Beall/Restall]
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
13134 We negate predicates but do not negate names [Westerhoff]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
10696 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
10693 Models are mathematical structures which interpret the non-logical primitives [Beall/Restall]
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
10692 Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall]
7. Existence / E. Categories / 1. Categories
13124 Categories can be ordered by both containment and generality [Westerhoff]
13117 How far down before we are too specialised to have a category? [Westerhoff]
13116 Maybe objects in the same category have the same criteria of identity [Westerhoff]
13118 Categories are base-sets which are used to construct states of affairs [Westerhoff]
13125 Categories are held to explain why some substitutions give falsehood, and others meaninglessness [Westerhoff]
13126 Categories systematize our intuitions about generality, substitutability, and identity [Westerhoff]
13130 Categories as generalities don't give a criterion for a low-level cut-off point [Westerhoff]
7. Existence / E. Categories / 2. Categorisation
13131 The aim is that everything should belong in some ontological category or other [Westerhoff]
7. Existence / E. Categories / 3. Proposed Categories
13123 All systems have properties and relations, and most have individuals, abstracta, sets and events [Westerhoff]
7. Existence / E. Categories / 5. Category Anti-Realism
13115 Ontological categories are like formal axioms, not unique and with necessary membership [Westerhoff]
13119 Categories merely systematise, and are not intrinsic to objects [Westerhoff]
13135 A thing's ontological category depends on what else exists, so it is contingent [Westerhoff]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
13132 A snowball's haecceity is the property of being identical with itself [Plantinga, by Westerhoff]
9. Objects / D. Essence of Objects / 5. Essence as Kind
13129 Essential kinds may be too specific to provide ontological categories [Westerhoff]