Combining Texts

All the ideas for 'Philosophical Essay on Probability', 'Mathematics is Megethology' and 'Identity and Existence in Logic'

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22 ideas

4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
Free logics has terms that do not designate real things, and even empty domains [Anderson,CA]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Mathematics reduces to set theory, which reduces, with some mereology, to the singleton function [Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
We can accept the null set, but not a null class, a class lacking members [Lewis]
The null set plays the role of last resort, for class abstracts and for existence [Lewis]
The null set is not a little speck of sheer nothingness, a black hole in Reality [Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
What on earth is the relationship between a singleton and an element? [Lewis]
Are all singletons exact intrinsic duplicates? [Lewis]
4. Formal Logic / G. Formal Mereology / 1. Mereology
Megethology is the result of adding plural quantification to mereology [Lewis]
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
We can use mereology to simulate quantification over relations [Lewis]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Basic variables in second-order logic are taken to range over subsets of the individuals [Anderson,CA]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
Stop calling ∃ the 'existential' quantifier, read it as 'there is...', and range over all entities [Anderson,CA]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Mathematics is generalisations about singleton functions [Lewis]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
We don't need 'abstract structures' to have structural truths about successor functions [Lewis]
7. Existence / A. Nature of Existence / 2. Types of Existence
Do mathematicians use 'existence' differently when they say some entity exists? [Anderson,CA]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
We can distinguish 'ontological' from 'existential' commitment, for different kinds of being [Anderson,CA]
9. Objects / A. Existence of Objects / 4. Impossible objects
's is non-existent' cannot be said if 's' does not designate [Anderson,CA]
We cannot pick out a thing and deny its existence, but we can say a concept doesn't correspond [Anderson,CA]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
Individuation was a problem for medievals, then Leibniz, then Frege, then Wittgenstein (somewhat) [Anderson,CA]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
I say that absolutely any things can have a mereological fusion [Lewis]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The notion of 'property' is unclear for a logical version of the Identity of Indiscernibles [Anderson,CA]
13. Knowledge Criteria / C. External Justification / 7. Testimony
The reliability of witnesses depends on whether they benefit from their observations [Laplace, by Hacking]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
If a supreme intellect knew all atoms and movements, it could know all of the past and the future [Laplace]