Combining Texts

All the ideas for 'Mahaprajnaparamitashastra', 'First-Order Logic' and 'Essential vs Accidental Properties'

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15 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
10282 Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
10283 A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
10284 There are three different standard presentations of semantics [Hodges,W]
10285 I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10288 Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
10289 Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
10287 If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
10286 A 'set' is a mathematically well-behaved class [Hodges,W]
9. Objects / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
10938 The extremes of essentialism are that all properties are essential, or only very trivial ones [Rami]
9. Objects / D. Essence of Objects / 3. Individual Essences
10940 An 'individual essence' is possessed uniquely by a particular object [Rami]
9. Objects / D. Essence of Objects / 5. Essence as Kind
10939 'Sortal essentialism' says being a particular kind is what is essential [Rami]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
10934 Unlosable properties are not the same as essential properties [Rami]
10. Modality / A. Necessity / 3. Types of Necessity
10933 Physical possibility is part of metaphysical possibility which is part of logical possibility [Rami]
10. Modality / B. Possibility / 2. Epistemic possibility
10932 If it is possible 'for all I know' then it is 'epistemically possible' [Rami]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
7903 The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]