Combining Philosophers

All the ideas for Rescher,N/Oppenheim,P, Shaughan Lavine and Stathis Psillos

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68 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Traditionally, rational beliefs are those which are justified by reasons [Psillos]
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 / 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]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
Valid deduction is monotonic - that is, it remains valid if further premises are added [Psillos]
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 theory of infinity must rest on our inability to distinguish between very large sizes [Lavine]
The infinite is extrapolation from the experience of indefinitely large size [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 / A. Nature of Existence / 6. Criterion for Existence
The 'epistemic fallacy' is inferring what does exist from what can be known to exist [Psillos]
8. Modes of Existence / B. Properties / 5. Natural Properties
Scientific properties are defined by the laws that embody them [Psillos, by Ladyman/Ross]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
Powers are claimed to be basic because fundamental particles lack internal structure [Psillos]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
A whole must have one characteristic, an internal relation, and a structure [Rescher/Oppenheim]
14. Science / A. Basis of Science / 4. Prediction
A good barometer will predict a storm, but not explain it [Psillos]
If we say where Mars was two months ago, we offer an explanation without a prediction [Psillos]
14. Science / C. Induction / 4. Reason in Induction
Induction (unlike deduction) is non-monotonic - it can be invalidated by new premises [Psillos]
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
Explanation is either showing predictability, or showing necessity, or showing causal relations [Psillos]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
Just citing a cause does not enable us to understand an event; we also need a relevant law [Psillos]
The 'covering law model' says only laws can explain the occurrence of single events [Psillos]
If laws explain the length of a flagpole's shadow, then the shadow also explains the length of the pole [Psillos]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
There are non-causal explanations, most typically mathematical explanations [Psillos]
An explanation can just be a 'causal story', without laws, as when I knock over some ink [Psillos]
14. Science / D. Explanation / 4. Explanation Doubts / a. Explanation as pragmatic
Maybe explanation is entirely relative to the interests and presuppositions of the questioner [Psillos]
An explanation is the removal of the surprise caused by the event [Psillos]
15. Nature of Minds / C. Capacities of Minds / 9. Perceiving Causation
It is hard to analyse causation, if it is presupposed in our theory of the functioning of the mind [Psillos]
22. Metaethics / B. Value / 1. Nature of Value / b. Fact and value
Nothing is more usual than to apply to external bodies every internal sensation which they occasion [Psillos]
26. Natural Theory / C. Causation / 1. Causation
We can't base our account of causation on explanation, because it is the wrong way round [Psillos]
Causes clearly make a difference, are recipes for events, explain effects, and are evidence [Psillos]
Theories of causation are based either on regularity, or on intrinsic relations of properties [Psillos]
26. Natural Theory / C. Causation / 2. Types of cause
Three divisions of causal theories: generalist/singularist, intrinsic/extrinsic, reductive/non-reductive [Psillos]
26. Natural Theory / C. Causation / 8. Particular Causation / b. Causal relata
If causation is 'intrinsic' it depends entirely on the properties and relations of the cause and effect [Psillos]
26. Natural Theory / C. Causation / 9. General Causation / b. Nomological causation
Empiricists tried to reduce causation to explanation, which they reduced to logic-plus-a-law [Psillos]
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
Counterfactual claims about causation imply that it is more than just regular succession [Psillos]
26. Natural Theory / D. Laws of Nature / 3. Laws and Generalities
"All gold cubes are smaller than one cubic mile" is a true universal generalisation, but not a law [Psillos]
26. Natural Theory / D. Laws of Nature / 4. Regularities / a. Regularity theory
Regularity doesn't seem sufficient for causation [Psillos]
A Humean view of causation says it is regularities, and causal facts supervene on non-causal facts [Psillos]
The regularity of a cock's crow is used to predict dawn, even though it doesn't cause it [Psillos]
It is not a law of nature that all the coins in my pocket are euros, though it is a regularity [Psillos]
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
Laws are sets of regularities within a simple and strong coherent system of wider regularities [Psillos]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / e. Anti scientific essentialism
Dispositional essentialism can't explain its key distinction between essential and non-essential properties [Psillos]
26. Natural Theory / D. Laws of Nature / 9. Counterfactual Claims
In some counterfactuals, the counterfactual event happens later than its consequent [Psillos]
Counterfactual theories say causes make a difference - if c hadn't occurred, then e wouldn't occur [Psillos]