Combining Texts

All the ideas for 'Elucidation of some points in E.Schröder', 'Function and Concept' and 'Intro to 'Philosophy of Logic''

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20 ideas

4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
Modal logic is multiple systems, shown in the variety of accessibility relations between worlds [Jacquette]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
A class is an aggregate of objects; if you destroy them, you destroy the class; there is no empty class [Frege]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
The two main views in philosophy of logic are extensionalism and intensionalism [Jacquette]
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
First-level functions have objects as arguments; second-level functions take functions as arguments [Frege]
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
Relations are functions with two arguments [Frege]
5. Theory of Logic / I. Semantics of Logic / 5. Extensionalism
Extensionalists say that quantifiers presuppose the existence of their objects [Jacquette]
5. Theory of Logic / I. Semantics of Logic / 6. Intensionalism
Intensionalists say meaning is determined by the possession of properties [Jacquette]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
Arithmetic is a development of logic, so arithmetical symbolism must expand into logical symbolism [Frege]
7. Existence / A. Nature of Existence / 6. Criterion for Existence
Frege takes the existence of horses to be part of their concept [Frege, by Sommers]
8. Modes of Existence / B. Properties / 10. Properties as Predicates
Frege allows either too few properties (as extensions) or too many (as predicates) [Mellor/Oliver on Frege]
9. Objects / A. Existence of Objects / 3. Objects in Thought
The concept 'object' is too simple for analysis; unlike a function, it is an expression with no empty place [Frege]
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
Concepts are the ontological counterparts of predicative expressions [Frege, by George/Velleman]
An assertion about the concept 'horse' must indirectly speak of an object [Frege, by Hale]
A concept is a function whose value is always a truth-value [Frege]
18. Thought / D. Concepts / 4. Structure of Concepts / a. Conceptual structure
Unlike objects, concepts are inherently incomplete [Frege, by George/Velleman]
19. Language / B. Reference / 5. Speaker's Reference
I may regard a thought about Phosphorus as true, and the same thought about Hesperus as false [Frege]
19. Language / C. Assigning Meanings / 7. Extensional Semantics
Extensionalist semantics forbids reference to nonexistent objects [Jacquette]
Extensionalist semantics is circular, as we must know the extension before assessing 'Fa' [Jacquette]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
The Ontological Argument fallaciously treats existence as a first-level concept [Frege]