Combining Texts

All the ideas for 'Logical Consequence', 'Things' and 'Identity and Essence'

expand these ideas     |    start again     |     specify just one area for these texts


22 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 / 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]
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
Bodies, properties, relations, events, numbers, sets and propositions are 'things' if they exist [Lowe]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
Indiscernibility is a necessary and sufficient condition for identity [Brody]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
Brody bases sortal essentialism on properties required throughout something's existence [Brody, by Mackie,P]
9. Objects / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
Modern emphasis is on properties had essentially; traditional emphasis is on sort-defining properties [Brody]
9. Objects / D. Essence of Objects / 5. Essence as Kind
A sortal essence is a property which once possessed always possessed [Brody, by Mackie,P]
Maybe essential properties are those which determine a natural kind? [Brody]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
De re essentialism standardly says all possible objects identical with a have a's essential properties [Brody]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
Essentially, a has P, always had P, must have had P, and has never had a future without P [Brody]
An object having a property essentially is equivalent to its having it necessarily [Brody]
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
Essentialism is justified if the essential properties of things explain their other properties [Brody]
9. Objects / D. Essence of Objects / 12. Essential Parts
Mereological essentialism says that every part that ensures the existence is essential [Brody]
9. Objects / E. Objects over Time / 12. Origin as Essential
Interrupted objects have two first moments of existence, which could be two beginnings [Brody]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
a and b share all properties; so they share being-identical-with-a; so a = b [Brody]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Identity across possible worlds is prior to rigid designation [Brody]