Combining Texts

All the ideas for 'works', 'Intro to 2nd ed of Principia Mathematica' and 'Writing the Book of the World'

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92 ideas

1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
Your metaphysics is 'cheating' if your ontology won't support the beliefs you accept [Sider]
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Metaphysics is not about what exists or is true or essential; it is about the structure of reality [Sider]
Extreme doubts about metaphysics also threaten to undermine the science of unobservables [Sider]
1. Philosophy / E. Nature of Metaphysics / 6. Metaphysics as Conceptual
It seems unlikely that the way we speak will give insights into the universe [Sider]
1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
Conceptual analysts trust particular intuitions much more than general ones [Sider]
2. Reason / D. Definition / 13. Against Definition
Philosophical concepts are rarely defined, and are not understood by means of definitions [Sider]
It seems possible for a correct definition to be factually incorrect, as in defining 'contact' [Sider]
3. Truth / A. Truth Problems / 3. Value of Truth
We don't care about plain truth, but truth in joint-carving terms [Sider]
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
Orthodox truthmaker theories make entities fundamental, but that is poor for explanation [Sider]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
The Barcan schema implies if X might have fathered something, there is something X might have fathered [Sider]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD]
Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg]
Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / d. Axiom of Unions III
The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / b. Combinatorial sets
Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley]
4. Formal Logic / G. Formal Mereology / 1. Mereology
'Gunk' is an object in which proper parts all endlessly have further proper parts [Sider]
4. Formal Logic / G. Formal Mereology / 3. Axioms of Mereology
Which should be primitive in mereology - part, or overlap? [Sider]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
There is a real issue over what is the 'correct' logic [Sider]
'It is raining' and 'it is not raining' can't be legislated, so we can't legislate 'p or ¬p' [Sider]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic is good for mathematics and science, but less good for natural language [Sider]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Modal accounts of logical consequence are simple necessity, or essential use of logical words [Sider]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
'Tonk' is supposed to follow the elimination and introduction rules, but it can't be so interpreted [Sider]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
There are infinite sets that are not enumerable [Cantor, by Smith,P]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / b. Cantor's paradox
Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / e. Mirimanoff's paradox
The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Cantor took the ordinal numbers to be primary [Cantor, by Tait]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / d. Natural numbers
Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait]
Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine]
Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine]
Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine]
It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner]
The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro]
Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD]
Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten]
Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS]
Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy]
Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Pure mathematics is pure set theory [Cantor]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Cantor says that maths originates only by abstraction from objects [Cantor, by Frege]
7. Existence / C. Structure of Existence / 5. Supervenience / a. Nature of supervenience
Supervenience is a modal connection [Sider]
7. Existence / C. Structure of Existence / 6. Fundamentals / b. Types of fundamental
Is fundamentality in whole propositions (and holistic), or in concepts (and atomic)? [Sider]
Tables and chairs have fundamental existence, but not fundamental natures [Sider]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Given all true atomic propositions, in theory every other truth can thereby be deduced [Russell]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Unlike things, stuff obeys unrestricted composition and mereological essentialism [Sider]
7. Existence / D. Theories of Reality / 9. States of Affairs
We must distinguish 'concrete' from 'abstract' and necessary states of affairs. [Sider]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / d. Commitment of theories
Accept the ontology of your best theory - and also that it carves nature at the joints [Sider]
8. Modes of Existence / B. Properties / 3. Types of Properties
A property is intrinsic if an object alone in the world can instantiate it [Sider]
8. Modes of Existence / B. Properties / 10. Properties as Predicates
Predicates can be 'sparse' if there is a universal, or if there is a natural property or relation [Sider]
9. Objects / D. Essence of Objects / 15. Against Essentialism
Essence (even if nonmodal) is not fundamental in metaphysics [Sider]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Modal terms in English are entirely contextual, with no modality outside the language [Sider]
Humeans say that we decide what is necessary [Sider]
10. Modality / C. Sources of Modality / 3. Necessity by Convention
Conventionalism doesn't seem to apply to examples of the necessary a posteriori [Sider]
If truths are necessary 'by convention', that seems to make them contingent [Sider]
10. Modality / C. Sources of Modality / 4. Necessity from Concepts
Humeans says mathematics and logic are necessary because that is how our concept of necessity works [Sider]
10. Modality / C. Sources of Modality / 5. Modality from Actuality
The world does not contain necessity and possibility - merely how things are [Sider]
14. Science / B. Scientific Theories / 2. Aim of Science
A theory which doesn't fit nature is unexplanatory, even if it is true [Sider]
14. Science / B. Scientific Theories / 8. Ramsey Sentences
If I used Ramsey sentences to eliminate fundamentality from my theory, that would be a real loss [Sider]
14. Science / C. Induction / 5. Paradoxes of Induction / a. Grue problem
Problem predicates in induction don't reflect the structure of nature [Sider]
Two applications of 'grue' do not guarantee a similarity between two things [Sider]
14. Science / C. Induction / 6. Bayes's Theorem
Bayes produces weird results if the prior probabilities are bizarre [Sider]
14. Science / D. Explanation / 1. Explanation / a. Explanation
Explanations must cite generalisations [Sider]
14. Science / D. Explanation / 3. Best Explanation / b. Ultimate explanation
If the ultimate explanation is a list of entities, no laws, patterns or mechanisms can be cited [Sider]
15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality
Intentionality is too superficial to appear in the catalogue of ultimate physics [Sider]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend]
18. Thought / E. Abstraction / 2. Abstracta by Selection
Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor]
19. Language / A. Nature of Meaning / 6. Meaning as Use
Prior to conventions, not all green things were green? [Sider]
19. Language / E. Analyticity / 2. Analytic Truths
Conventions are contingent and analytic truths are necessary, so that isn't their explanation [Sider]
19. Language / E. Analyticity / 4. Analytic/Synthetic Critique
Analyticity has lost its traditional role, which relied on truth by convention [Sider]
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
Many of the key theories of modern physics do not appear to be 'laws' [Sider]
The notion of law doesn't seem to enhance physical theories [Sider]
27. Natural Reality / C. Space / 3. Points in Space
Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg]
27. Natural Reality / C. Space / 4. Substantival Space
Space has real betweenness and congruence structure (though it is not the Euclidean concepts) [Sider]
27. Natural Reality / C. Space / 6. Space-Time
The central question in the philosophy of time is: How alike are time and space? [Sider]
27. Natural Reality / D. Time / 1. Nature of Time / f. Eternalism
The spotlight theorists accepts eternal time, but with a spotlight of the present moving across it [Sider]
28. God / A. Divine Nature / 2. Divine Nature
Only God is absolutely infinite [Cantor, by Hart,WD]