Combining Texts

All the ideas for 'Locke on Essences and Kinds', 'The Identity of Indiscernibles' and 'Grundgesetze der Arithmetik 2 (Basic Laws)'

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20 ideas

2. Reason / D. Definition / 2. Aims of Definition
Later Frege held that definitions must fix a function's value for every possible argument [Frege, by Wright,C]
2. Reason / D. Definition / 7. Contextual Definition
We can't define a word by defining an expression containing it, as the remaining parts are a problem [Frege]
2. Reason / D. Definition / 11. Ostensive Definition
Only what is logically complex can be defined; what is simple must be pointed to [Frege]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice needs a criterion of choice [Black]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cardinals say how many, and reals give measurements compared to a unit quantity [Frege]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Real numbers are ratios of quantities [Frege, by Dummett]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
A number is a class of classes of the same cardinality [Frege, by Dummett]
Frege's biggest error is in not accounting for the senses of number terms [Hodes on Frege]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Formalism misunderstands applications, metatheory, and infinity [Frege, by Dummett]
Only applicability raises arithmetic from a game to a science [Frege]
9. Objects / A. Existence of Objects / 5. Individuation / b. Individuation by properties
Two things can only be distinguished by a distinct property or a distinct relation [Black]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
The first demand of logic is of a sharp boundary [Frege]
9. Objects / D. Essence of Objects / 13. Nominal Essence
If kinds depend only on what can be observed, many underlying essences might produce the same kind [Eagle]
Nominal essence are the observable properties of things [Eagle]
Nominal essence mistakenly gives equal weight to all underlying properties that produce appearances [Eagle]
9. Objects / F. Identity among Objects / 5. Self-Identity
The 'property' of self-identity is uselessly tautological [Black]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
If the universe just held two indiscernibles spheres, that refutes the Identity of Indiscernibles [Black]
18. Thought / E. Abstraction / 3. Abstracta by Ignoring
The modern account of real numbers detaches a ratio from its geometrical origins [Frege]
18. Thought / E. Abstraction / 8. Abstractionism Critique
If we abstract the difference between two houses, they don't become the same house [Frege]
26. Natural Theory / B. Natural Kinds / 4. Source of Kinds
Kinds are fixed by the essential properties of things - the properties that make it that kind of thing [Eagle]