Combining Texts

All the ideas for 'Posthumous notes', 'Understanding the Infinite' and 'A Powerful Particulars View of Causation'

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


66 ideas

1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Metaphysics can criticise interpretations of science theories, and give good feedback [Ingthorsson]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Second-order set theory just adds a version of Replacement that quantifies over functions [Lavine]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
An 'upper bound' is the greatest member of a subset; there may be several of these, so there is a 'least' one [Lavine]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
Collections of things can't be too big, but collections by a rule seem unlimited in size [Lavine]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
Those who reject infinite collections also want to reject the Axiom of Choice [Lavine]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / g. Axiom of Powers VI
The Power Set is just the collection of functions from one collection to another [Lavine]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Replacement was immediately accepted, despite having very few implications [Lavine]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
Foundation says descending chains are of finite length, blocking circularity, or ungrounded sets [Lavine]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
Pure collections of things obey Choice, but collections defined by a rule may not [Lavine]
The controversy was not about the Axiom of Choice, but about functions as arbitrary, or given by rules [Lavine]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
The 'logical' notion of class has some kind of definition or rule to characterise the class [Lavine]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception of set wasn't suggested until 1947 [Lavine]
The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine]
The iterative conception doesn't unify the axioms, and has had little impact on mathematical proofs [Lavine]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
Limitation of Size: if it's the same size as a set, it's a set; it uses Replacement [Lavine]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
A collection is 'well-ordered' if there is a least element, and all of its successors can be identified [Lavine]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Philosophers accepted first-order logic, because they took science to be descriptive, not explanatory [Ingthorsson]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order logic presupposes a set of relations already fixed by the first-order domain [Lavine]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Mathematical proof by contradiction needs the law of excluded middle [Lavine]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Mathematics is nowadays (thanks to set theory) regarded as the study of structure, not of quantity [Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Every rational number, unlike every natural number, is divisible by some other number [Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
For the real numbers to form a set, we need the Continuum Hypothesis to be true [Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
Cauchy gave a necessary condition for the convergence of a sequence [Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
The two sides of the Cut are, roughly, the bounding commensurable ratios [Lavine]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Counting results in well-ordering, and well-ordering makes counting possible [Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
The infinite is extrapolation from the experience of indefinitely large size [Lavine]
The theory of infinity must rest on our inability to distinguish between very large sizes [Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / c. Potential infinite
The intuitionist endorses only the potential infinite [Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
'Aleph-0' is cardinality of the naturals, 'aleph-1' the next cardinal, 'aleph-ω' the ω-th cardinal [Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Ordinals are basic to Cantor's transfinite, to count the sets [Lavine]
Paradox: the class of all ordinals is well-ordered, so must have an ordinal as type - giving a bigger ordinal [Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Paradox: there is no largest cardinal, but the class of everything seems to be the largest [Lavine]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set theory will found all of mathematics - except for the notion of proof [Lavine]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
Modern mathematics works up to isomorphism, and doesn't care what things 'really are' [Lavine]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionism rejects set-theory to found mathematics [Lavine]
7. Existence / B. Change in Existence / 2. Processes
Basic processes are said to be either physical, or organic, or psychological [Ingthorsson]
7. Existence / D. Theories of Reality / 2. Realism
Indirect realists are cautious about the manifest image, and prefer the scientific image [Ingthorsson]
8. Modes of Existence / A. Relations / 1. Nature of Relations
Neo-Humeans say there are no substantial connections between anything [Ingthorsson]
8. Modes of Existence / B. Properties / 3. Types of Properties
Properties are said to be categorical qualities or non-qualitative dispositions [Ingthorsson]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
Physics understands the charge of an electron as a power, not as a quality [Ingthorsson]
9. Objects / A. Existence of Objects / 1. Physical Objects
Compound objects are processes, insofar as change is essential to them [Ingthorsson]
9. Objects / A. Existence of Objects / 5. Simples
Most materialist views postulate smallest indivisible components which are permanent [Ingthorsson]
9. Objects / E. Objects over Time / 1. Objects over Time
Endurance and perdurance just show the consequences of A or B series time [Ingthorsson]
Science suggests causal aspects of the constitution and persistance of objects [Ingthorsson]
9. Objects / E. Objects over Time / 4. Four-Dimensionalism
If causation involves production, that needs persisting objects [Ingthorsson]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Every philosophical theory must be true in some possible world, so the ontology is hopeless [Ingthorsson]
Worlds may differ in various respects, but no overall similarity of worlds is implied [Ingthorsson]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
Transcendental philosophy is the subject becoming the originator of unified reality [Kant]
26. Natural Theory / C. Causation / 2. Types of cause
Humeans describe the surface of causation, while powers accounts aim at deeper explanations [Ingthorsson]
Time and space are not causal, but they determine natural phenomena [Ingthorsson]
26. Natural Theory / C. Causation / 4. Naturalised causation
Casuation is the transmission of conserved quantities between causal processes [Ingthorsson]
Interventionist causal theory says it gets a reliable result whenever you manipulate it [Ingthorsson]
Causation as transfer only works for asymmetric interactions [Ingthorsson]
26. Natural Theory / C. Causation / 8. Particular Causation / b. Causal relata
Causal events are always reciprocal, and there is no distinction of action and reaction [Ingthorsson]
One effect cannot act on a second effect in causation, because the second doesn't yet exist [Ingthorsson]
Empiricists preferred events to objects as the relata, because they have observable motions [Ingthorsson]
Science now says all actions are reciprocal, not unidirectional [Ingthorsson]
Causes are not agents; the whole interaction is the cause, and the changed compound is the effect [Ingthorsson]
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
People only accept the counterfactual when they know the underlying cause [Ingthorsson]
Counterfactuals don't explain causation, but causation can explain counterfactuals [Ingthorsson]
Counterfactual theories are false in possible worlds where causation is actual [Ingthorsson]
26. Natural Theory / C. Causation / 9. General Causation / d. Causal necessity
A cause can fail to produce its normal effect, by prevention, pre-emption, finks or antidotes [Ingthorsson]
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
Any process can go backwards or forwards in time without violating the basic laws of physics [Ingthorsson]
27. Natural Reality / A. Classical Physics / 1. Mechanics / b. Laws of motion
In modern physics the first and second laws of motion (unlike the third) fail at extremes [Ingthorsson]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
If particles have decay rates, they can't really be elementary, in the sense of indivisible [Ingthorsson]
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
It is difficult to handle presentism in first-order logic [Ingthorsson]