Combining Texts

All the ideas for '', 'Elements of Set Theory' and 'Disputationes metaphysicae'

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28 ideas

4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
∈ says the whole set is in the other; ⊆ says the members of the subset are in the other [Enderton]
The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [Enderton]
A 'linear or total ordering' must be transitive and satisfy trichotomy [Enderton]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Note that {Φ} =/= Φ, because Φ ∈ {Φ} but Φ ∉ Φ [Enderton]
The empty set may look pointless, but many sets can be constructed from it [Enderton]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
The singleton is defined using the pairing axiom (as {x,x}) [Enderton]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Fraenkel added Replacement, to give a theory of ordinal numbers [Enderton]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
We can only define functions if Choice tells us which items are involved [Enderton]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
8. Modes of Existence / B. Properties / 8. Properties as Modes
There are entities, and then positive 'modes', modifying aspects outside the thing's essence [Suárez]
A mode determines the state and character of a quantity, without adding to it [Suárez]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Substances are incomplete unless they have modes [Suárez, by Pasnau]
9. Objects / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
Forms must rule over faculties and accidents, and are the source of action and unity [Suárez]
9. Objects / C. Structure of Objects / 2. Hylomorphism / d. Form as unifier
Partial forms of leaf and fruit are united in the whole form of the tree [Suárez]
The best support for substantial forms is the co-ordinated unity of a natural being [Suárez]
9. Objects / C. Structure of Objects / 4. Quantity of an Object
We can get at the essential nature of 'quantity' by knowing bulk and extension [Suárez]
9. Objects / D. Essence of Objects / 14. Knowledge of Essences
We only know essences through non-essential features, esp. those closest to the essence [Suárez]
9. Objects / F. Identity among Objects / 1. Concept of Identity
Identity does not exclude possible or imagined difference [Suárez, by Boulter]
Real Essential distinction: A and B are of different natural kinds [Suárez, by Boulter]
Minor Real distinction: B needs A, but A doesn't need B [Suárez, by Boulter]
Major Real distinction: A and B have independent existences [Suárez, by Boulter]
Conceptual/Mental distinction: one thing can be conceived of in two different ways [Suárez, by Boulter]
Modal distinction: A isn't B or its property, but still needs B [Suárez, by Boulter]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
Scholastics assess possibility by what has actually happened in reality [Suárez, by Boulter]
19. Language / F. Communication / 3. Denial
We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
29. Religion / B. Monotheistic Religion / 4. Christianity / c. Angels
Other things could occupy the same location as an angel [Suárez]