Combining Texts

All the ideas for 'Structures and Structuralism in Phil of Maths', 'First-Order Logic' and 'On Sense and Reference'

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


59 ideas

3. Truth / A. Truth Problems / 5. Truth Bearers
Frege was strongly in favour of taking truth to attach to propositions [Frege, by Dummett]
3. Truth / F. Semantic Truth / 2. Semantic Truth
While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
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 / F. Referring in Logic / 1. Naming / a. Names
We can treat designation by a few words as a proper name [Frege]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
A Fregean proper name has a sense determining an object, instead of a concept [Frege, by Sainsbury]
People may have different senses for 'Aristotle', like 'pupil of Plato' or 'teacher of Alexander' [Frege]
Proper name in modal contexts refer obliquely, to their usual sense [Frege, by Gibbard]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
The meaning of a proper name is the designated object [Frege]
5. Theory of Logic / F. Referring in Logic / 1. Naming / d. Singular terms
Frege ascribes reference to incomplete expressions, as well as to singular terms [Frege, by Hale]
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
If sentences have a 'sense', empty name sentences can be understood that way [Frege, by Sawyer]
It is a weakness of natural languages to contain non-denoting names [Frege]
In a logically perfect language every well-formed proper name designates an object [Frege]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
There are three different standard presentations of semantics [Hodges,W]
I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 6. Intensionalism
Frege is intensionalist about reference, as it is determined by sense; identity of objects comes first [Frege, by Jacquette]
Frege moved from extensional to intensional semantics when he added the idea of 'sense' [Frege, by Sawyer]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
'Analysis' is the theory of the real numbers [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Mereological arithmetic needs infinite objects, and function definitions [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set-theory gives a unified and an explicit basis for mathematics [Reck/Price]
A 'set' is a mathematically well-behaved class [Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / b. Varieties of structuralism
Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price]
There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price]
Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price]
There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price]
Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price]
Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price]
8. Modes of Existence / D. Universals / 1. Universals
We can't get a semantics from nouns and predicates referring to the same thing [Frege, by Dummett]
8. Modes of Existence / E. Nominalism / 6. Mereological Nominalism
A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price]
9. Objects / F. Identity among Objects / 1. Concept of Identity
Frege was asking how identities could be informative [Frege, by Perry]
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
'The concept "horse"' denotes a concept, yet seems also to denote an object [Frege, by McGee]
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Frege failed to show when two sets of truth-conditions are equivalent [Frege, by Potter]
The meaning (reference) of a sentence is its truth value - the circumstance of it being true or false [Frege]
19. Language / A. Nature of Meaning / 7. Meaning Holism / b. Language holism
Holism says all language use is also a change in the rules of language [Frege, by Dummett]
19. Language / B. Reference / 1. Reference theories
The reference of a word should be understood as part of the reference of the sentence [Frege]
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
Frege's Puzzle: from different semantics we infer different reference for two names with the same reference [Frege, by Fine,K]
Frege's 'sense' is ambiguous, between the meaning of a designator, and how it fixes reference [Kripke on Frege]
Every descriptive name has a sense, but may not have a reference [Frege]
Frege started as anti-realist, but the sense/reference distinction led him to realism [Frege, by Benardete,JA]
The meaning (reference) of 'evening star' is the same as that of 'morning star', but not the sense [Frege]
In maths, there are phrases with a clear sense, but no actual reference [Frege]
We are driven from sense to reference by our desire for truth [Frege]
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
Expressions always give ways of thinking of referents, rather than the referents themselves [Frege, by Soames]
19. Language / C. Assigning Meanings / 5. Fregean Semantics
'Sense' gives meaning to non-referring names, and to two expressions for one referent [Frege, by Margolis/Laurence]
Frege was the first to construct a plausible theory of meaning [Frege, by Dummett]
Earlier Frege focuses on content itself; later he became interested in understanding content [Frege, by Dummett]
Frege divided the meaning of a sentence into sense, force and tone [Frege, by Dummett]
Frege uses 'sense' to mean both a designator's meaning, and the way its reference is determined [Kripke on Frege]
Frege explained meaning as sense, semantic value, reference, force and tone [Frege, by Miller,A]