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All the ideas for 'Confessions', 'Contemporary Political Philosophy (2nd edn)' and 'works'

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86 ideas

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]
     Full Idea: The notion of a function evolved gradually from wanting to see what curves can be represented as trigonometric series. The study of arbitrary functions led Cantor to the ordinal numbers, which led to set theory.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite I
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]
     Full Idea: Cantor's Theorem says that for any set x, its power set P(x) has more members than x.
     From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1
Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock]
     Full Idea: Cantor's diagonalisation argument generalises to show that any set has more subsets than it has members.
     From: report of George Cantor (works [1880]) by David Bostock - Philosophy of Mathematics 4.5
     A reaction: Thus three members will generate seven subsets. This means that 'there is no end to the series of cardinal numbers' (Bostock p.106).
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]
     Full Idea: Cantor taught that a set is 'a many, which can be thought of as one'. ...After a time the unfortunate beginner student is told that some classes - the singletons - have only a single member. Here is a just cause for student protest, if ever there was one.
     From: report of George Cantor (works [1880]) by David Lewis - Parts of Classes 2.1
     A reaction: There is a parallel question, almost lost in the mists of time, of whether 'one' is a number. 'Zero' is obviously dubious, but if numbers are for counting, that needs units, so the unit is the precondition of counting, not part of it.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter]
     Full Idea: Cantor's theories exhibited the contradictions others had claimed to derive from the supposition of infinite sets as confusions resulting from the failure to mark the necessary distinctions with sufficient clarity.
     From: report of George Cantor (works [1880]) by Michael Potter - Set Theory and Its Philosophy Intro 1
The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg]
     Full Idea: Cantor discovered that the continuum is the powerset of the integers. While adding or multiplying infinities didn't move up a level of complexity, multiplying a number by itself an infinite number of times did.
     From: report of George Cantor (works [1880]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.14
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]
     Full Idea: Cantor first stated the Union Axiom in a letter to Dedekind in 1899. It is nearly too obvious to deserve comment from most commentators. Justifications usually rest on 'limitation of size' or on the 'iterative conception'.
     From: report of George Cantor (works [1880]) by Penelope Maddy - Believing the Axioms I §1.3
     A reaction: Surely someone can think of some way to challenge it! An opportunity to become notorious, and get invited to conferences.
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]
     Full Idea: Cantor's definition of a set was a collection of its members into a whole, but within a few years Dedekind had the idea of a set as a container, enclosing its members like a sack.
     From: report of George Cantor (works [1880]) by Oliver,A/Smiley,T - What are Sets and What are they For? Intro
     A reaction: As the article goes on to show, these two view don't seem significantly different until you start to ask about the status of the null set and of singletons. I intuitively vote for Dedekind. Set theory is the study of brackets.
5. Theory of Logic / K. Features of Logics / 8. Enumerability
There are infinite sets that are not enumerable [Cantor, by Smith,P]
     Full Idea: Cantor's Theorem (1874) says there are infinite sets that are not enumerable. This is proved by his 1891 'diagonal argument'.
     From: report of George Cantor (works [1880]) by Peter Smith - Intro to Gödel's Theorems 2.3
     A reaction: [Smith summarises the diagonal argument]
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]
     Full Idea: The problem of Cantor's Paradox is that the power set of the universe has to be both bigger than the universe (by Cantor's theorem) and not bigger (since it is a subset of the universe).
     From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 3
     A reaction: Russell eliminates the 'universe' in his theory of types. I don't see why you can't just say that the members of the set are hypothetical rather than real, and that hypothetically the universe might contain more things than it does.
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]
     Full Idea: Cantor's Paradox says that the powerset of a set has a cardinal number strictly greater than the original set, but that means that the powerset of the set of all the cardinal numbers is greater than itself.
     From: report of George Cantor (works [1880]) by Michèle Friend - Introducing the Philosophy of Mathematics
     A reaction: Friend cites this with the Burali-Forti paradox and the Russell paradox as the best examples of the problems of set theory in the early twentieth century. Did this mean that sets misdescribe reality, or that we had constructed them wrongly?
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine]
     Full Idea: Cantor believed he had discovered that between the finite and the 'Absolute', which is 'incomprehensible to the human understanding', there is a third category, which he called 'the transfinite'.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.4
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]
     Full Idea: In 1878 Cantor published the unexpected result that one can put the points on a plane, or indeed any n-dimensional space, into one-to-one correspondence with the points on a line.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.1
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]
     Full Idea: Cantor took the ordinal numbers to be primary: in his generalization of the cardinals and ordinals into the transfinite, it is the ordinals that he calls 'numbers'.
     From: report of George Cantor (works [1880]) by William W. Tait - Frege versus Cantor and Dedekind VI
     A reaction: [Tait says Dedekind also favours the ordinals] It is unclear how the matter might be settled. Humans cannot give the cardinality of large groups without counting up through the ordinals. A cardinal gets its meaning from its place in the ordinals?
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]
     Full Idea: Cantor taught us to regard the totality of natural numbers, which was formerly thought to be infinite, as really finite after all.
     From: report of George Cantor (works [1880]) by John Mayberry - What Required for Foundation for Maths? p.414-2
     A reaction: I presume this is because they are (by definition) countable.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait]
     Full Idea: Cantor introduced the distinction between cardinal and ordinal numbers.
     From: report of George Cantor (works [1880]) by William W. Tait - Frege versus Cantor and Dedekind Intro
     A reaction: This seems remarkably late for what looks like a very significant clarification. The two concepts coincide in finite cases, but come apart in infinite cases (Tait p.58).
Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett]
     Full Idea: Cantor's work revealed that the notion of an ordinal number is more fundamental than that of a cardinal number.
     From: report of George Cantor (works [1880]) by Michael Dummett - Frege philosophy of mathematics Ch.23
     A reaction: Dummett makes it sound like a proof, which I find hard to believe. Is the notion that I have 'more' sheep than you logically prior to how many sheep we have? If I have one more, that implies the next number, whatever that number may be. Hm.
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]
     Full Idea: The cardinal number of M is the general idea which, by means of our active faculty of thought, is deduced from the collection M, by abstracting from the nature of its diverse elements and from the order in which they are given.
     From: George Cantor (works [1880]), quoted by Bertrand Russell - The Principles of Mathematics §284
     A reaction: [Russell cites 'Math. Annalen, XLVI, §1'] See Fine 1998 on this.
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]
     Full Idea: Cantor said he could show that every infinite set of points on the line could be placed into one-to-one correspondence with either the natural numbers or the real numbers - with no intermediate possibilies (the Continuum hypothesis). His proof failed.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.1
Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read]
     Full Idea: Cantor's diagonal argument showed that all the infinite decimals between 0 and 1 cannot be written down even in a single never-ending list.
     From: report of George Cantor (works [1880]) by Stephen Read - Thinking About Logic Ch.6
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]
     Full Idea: Cantor's theory of Cauchy sequences defines a real number to be associated with an infinite set of infinite sequences of rational numbers.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite II.6
     A reaction: This sounds remarkably like the endless decimals we use when we try to write down an actual real number.
Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine]
     Full Idea: Cantor introduced irrationals to play the role of limits of Cauchy sequences of rational numbers.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite 4.2
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]
     Full Idea: From the very nature of an irrational number, it seems necessary to understand the mathematical infinite thoroughly before an adequate theory of irrationals is possible. Infinite classes are obvious in the Dedekind Cut, but have logical difficulties
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite II Intro
     A reaction: Almost the whole theory of analysis (calculus) rested on the irrationals, so a theory of the infinite was suddenly (in the 1870s) vital for mathematics. Cantor wasn't just being eccentric or mystical.
It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine]
     Full Idea: Cantor's 1891 diagonal argument revealed there are infinitely many infinite powers. Indeed, it showed more: it shows that given any set there is another of greater power. Hence there is an infinite power strictly greater than that of the set of the reals.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.2
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]
     Full Idea: What we might call 'Cantor's Thesis' is that there won't be a potential infinity of any sort unless there is an actual infinity of some sort.
     From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1
     A reaction: This idea is nicely calculated to stop Aristotle in his tracks.
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]
     Full Idea: Cantor showed that the complete totality of natural numbers cannot be mapped 1-1 onto the complete totality of the real numbers - so there are different sizes of infinity.
     From: report of George Cantor (works [1880]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.4
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]
     Full Idea: Cantor's Continuum Hypothesis (CH) says that for every infinite set X of reals there is either a one-to-one correspondence between X and the natural numbers, or between X and the real numbers.
     From: report of George Cantor (works [1880]) by Peter Koellner - On the Question of Absolute Undecidability 1.2
     A reaction: Every single writer I read defines this differently, which drives me crazy, but is also helpfully illuminating. There is a moral there somewhere.
The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro]
     Full Idea: Cantor's 'continuum hypothesis' is the assertion that there are no infinite cardinalities strictly between the size of the natural numbers and the size of the real numbers.
     From: report of George Cantor (works [1880]) by Stewart Shapiro - Thinking About Mathematics 2.4
     A reaction: The tricky question is whether this hypothesis can be proved.
Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD]
     Full Idea: Cantor conjectured that there is no size between those of the naturals and the reals - called the 'continuum hypothesis'. The generalized version says that for no infinite set A is there a set larger than A but smaller than P(A).
     From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1
     A reaction: Thus there are gaps between infinite numbers, and the power set is the next size up from any infinity. Much discussion as ensued about whether these two can be proved.
Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten]
     Full Idea: Cantor's Continuum Hypothesis states that there are no sets which are too large for there to be a one-to-one correspondence between the set and the natural numbers, but too small for there to exist a one-to-one correspondence with the real numbers.
     From: report of George Cantor (works [1880]) by Leon Horsten - Philosophy of Mathematics §5.1
Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS]
     Full Idea: Cantor's conjecture (the Continuum Hypothesis) is that there are no sets between N and P(N). The 'generalized' version replaces N with an arbitrary infinite set.
     From: report of George Cantor (works [1880]) by Robert S. Wolf - A Tour through Mathematical Logic 2.2
     A reaction: The initial impression is that there is a single gap in the numbers, like a hole in ozone layer, but the generalised version implies an infinity of gaps. How can there be gaps in the numbers? Weird.
Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara]
     Full Idea: Cantor's Continuum Hypothesis was that there is no cardinal number greater than aleph-null but less than the cardinality of the continuum.
     From: report of George Cantor (works [1880]) by Charles Chihara - A Structural Account of Mathematics 05.1
     A reaction: I have no view on this (have you?), but the proposal that there are gaps in the number sequences has to excite all philosophers.
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]
     Full Idea: Cantor's second innovation was to extend the sequence of ordinal numbers into the transfinite, forming a handy scale for measuring infinite cardinalities.
     From: report of George Cantor (works [1880]) by Penelope Maddy - Naturalism in Mathematics I.1
     A reaction: Struggling with this. The ordinals seem to locate the cardinals, but in what sense do they 'measure' them?
Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine]
     Full Idea: Cantor's set theory was not of collections in some familiar sense, but of collections that can be counted using the indexes - the finite and transfinite ordinal numbers. ..He treated infinite collections as if they were finite.
     From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite I
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]
     Full Idea: Cantor's first innovation was to treat cardinality as strictly a matter of one-to-one correspondence, so that the question of whether two infinite sets are or aren't of the same size suddenly makes sense.
     From: report of George Cantor (works [1880]) by Penelope Maddy - Naturalism in Mathematics I.1
     A reaction: It makes sense, except that all sets which are infinite but countable can be put into one-to-one correspondence with one another. What's that all about, then?
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]
     Full Idea: Cantor's theorem entails that there are more property extensions than objects. So there are not enough objects in any domain to serve as extensions for that domain. So Frege's view that numbers are objects led to the Caesar problem.
     From: report of George Cantor (works [1880]) by Stewart Shapiro - Philosophy of Mathematics 4.6
     A reaction: So the possibility that Caesar might have to be a number arises because otherwise we are threatening to run out of numbers? Is that really the problem?
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Pure mathematics is pure set theory [Cantor]
     Full Idea: Pure mathematics ...according to my conception is nothing other than pure set theory.
     From: George Cantor (works [1880], I.1), quoted by Penelope Maddy - Naturalism in Mathematics I.1
     A reaction: [an unpublished paper of 1884] So right at the beginning of set theory this claim was being made, before it was axiomatised, and so on. Zermelo endorsed the view, and it flourished unchallenged until Benacerraf (1965).
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]
     Full Idea: Cantor calls mathematics an empirical science in so far as it begins with consideration of things in the external world; on his view, number originates only by abstraction from objects.
     From: report of George Cantor (works [1880]) by Gottlob Frege - Grundlagen der Arithmetik (Foundations) §21
     A reaction: Frege utterly opposed this view, and he seems to have won the day, but I am rather thrilled to find the great Cantor endorsing my own intuitions on the subject. The difficulty is to explain 'abstraction'.
7. Existence / A. Nature of Existence / 2. Types of Existence
I prefer a lack of form to mean non-existence, than to think of some quasi-existence [Augustine]
     Full Idea: I sooner judged that what lacks all form does not exist, than thought of as something in between form and nothing, neither formed nor nothing, unformed and next to nothing.
     From: Augustine (Confessions [c.398], XII.6), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 03.1
     A reaction: Scholastics were struck by the contrast between this remark, and the remark of Averroes (Idea 16587) that prime matter was halfway existence. Their two great authorities disagreed! This sort of thing stimulated the revival of metaphysics.
7. Existence / D. Theories of Reality / 1. Ontologies
Three main questions seem to be whether a thing is, what it is, and what sort it is [Augustine]
     Full Idea: I am told that I can ask three sorts of questions - whether a thing is, what it is, and what sort it is.
     From: Augustine (Confessions [c.398], X.10)
     A reaction: This seems to be a very Aristotelian approach. I am pleased to see that what it is and what sort it is are not conflated. The first one must be its individual essence, and the second its generic essence.
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
I can distinguish different smells even when I am not experiencing them [Augustine]
     Full Idea: I can distinguish the scent of lilies from that of violets, even though there is no scent at all in my nostrils.
     From: Augustine (Confessions [c.398], X.08)
     A reaction: Augustine has a nice introspective account of how we experience memory, and identifies lots of puzzling features. I know I can identify the smell of vinegar, but I can't bring it to mind, the way I can the appearance of roses.
Why does joy in my mind make me happy, but joy in my memory doesn't? [Augustine]
     Full Idea: How can it be that my mind can be happy because of the joy that is in it, and yet my memory is not sad by reason of the sadness that is in it?
     From: Augustine (Confessions [c.398], X.14)
     A reaction: This seems to contradict his thought in Idea 22981, that memory and mind are the same. Recall seems to be a part of consciousness which is not fully wired up to the rest of the mind.
Mind and memory are the same, as shown in 'bear it in mind' or 'it slipped from mind' [Augustine]
     Full Idea: The mind and the memory are one and the same. We even call the memory the mind, for when we tell a person to remember something, we tell them to 'bear this in mind', and when we forget something 'it slipped out of my mind'.
     From: Augustine (Confessions [c.398], X.14)
     A reaction: This idea has become familiar in modern neuroscience, I think, presumably because we do not find distinct types of neurons for consciousness and for memory.
We would avoid remembering sorrow or fear if that triggered the emotions afresh [Augustine]
     Full Idea: If we had to experience sorrow or fear every time that we mentioned these emotions, no one would be willing to speak of them.
     From: Augustine (Confessions [c.398], X.14)
     A reaction: Remembering the death of a loved one can trigger fresh grief, but remembering their dangerous illness from which they recovered no longer contains the feeling of fear.
Memory contains innumerable principles of maths, as well as past sense experiences [Augustine]
     Full Idea: The memory contains the innumerable principles and laws of numbers and dimensions. None of these can have been conveyed to me by the bodily senses.
     From: Augustine (Confessions [c.398], X.12)
     A reaction: Even if you have a fairly empirical view of the sources of mathematics (a view with which I sympathise), it must by admitted that our endless extrapolations from the sources also reside in memory. So we remember thoughts as well as experiences.
15. Nature of Minds / A. Nature of Mind / 6. Anti-Individualism
Memory is so vast that I cannot recognise it as part of my mind [Augustine]
     Full Idea: The memory is a vast immeasurable sanctuary. It is part of my nature, but I cannot understand all that I am. Hence the mind is too narrow to contain itself entirely. Is the other part outside of itself, and not within it? How then can it be a part?
     From: Augustine (Confessions [c.398], X.08)
     A reaction: He seems to understand the mind as entirely consisting of consciousness. Nevertheless, this seems to be the first inklings of the modern externalist view of the mind.
16. Persons / D. Continuity of the Self / 2. Mental Continuity / a. Memory is Self
Without memory I could not even speak of myself [Augustine]
     Full Idea: I do not understand the power of memory that is in myself, although without it I could not even speak of myself.
     From: Augustine (Confessions [c.398], X.16)
     A reaction: Even if the self is not identical with memory, this idea seems to establish that memory is an essential aspect of the self. This point is neglected by those who see the self as an entity (the 'soul pearl') which persists through all experience.
16. Persons / F. Free Will / 6. Determinism / a. Determinism
If the future does not exist, how can prophets see it? [Augustine]
     Full Idea: How do prophets see the future, if there is not a future to be seen?
     From: Augustine (Confessions [c.398], XI.17)
     A reaction: The answer, I suspect, is that prophets can't see the future. The prospect that the future already exists would seem to saboutage human freedom and responsibility, and point to Calvinist predestination, and even fatalism.
18. Thought / B. Mechanics of Thought / 5. Mental Files
Memories are preserved separately, according to category [Augustine]
     Full Idea: In memory everything is preserved separately, according to its category.
     From: Augustine (Confessions [c.398], X.08)
     A reaction: This strikes me as the first seeds of the idea that the mind functions by means of mental files. Our memories of cats are 'close to' or 'linked to' our memories of dogs.
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]
     Full Idea: Cantor (in his exploration of infinities) pushed the bounds of conceivability further than anyone before him. To discover what is conceivable, we have to enquire into the concept.
     From: report of George Cantor (works [1880]) by Michèle Friend - Introducing the Philosophy of Mathematics 6.5
     A reaction: This remark comes during a discussion of Husserl's phenomenology. Intuitionists challenge Cantor's claim, and restrict what is conceivable to what is provable. Does possibility depend on conceivability?
18. Thought / E. Abstraction / 2. Abstracta by Selection
Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor]
     Full Idea: Cantor thought that we abstract a number as something common to all and only those sets any one of which has as many members as any other. ...However one wants to see the logic of the inference. The irony is that set theory lays out this logic.
     From: comment on George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1
     A reaction: The logic Hart has in mind is the notion of an equivalence relation between sets. This idea sums up the older and more modern concepts of abstraction, the first as psychological, the second as logical (or trying very hard to be!). Cf Idea 9145.
22. Metaethics / C. The Good / 2. Happiness / c. Value of happiness
Everyone wants happiness [Augustine]
     Full Idea: Surely happiness is what everyone wants, so much so that there can be none who do not want it?
     From: Augustine (Confessions [c.398], X.20)
     A reaction: His concept of happiness is, of course, religious. Occasionally you meet habitual grumblers about life who give the impression that they are only happy when they are discontented. So happiness is achieving desires, not feeling good?
24. Political Theory / B. Nature of a State / 4. Citizenship
Some liberals thinks checks and balances are enough, without virtuous citizens [Kymlicka]
     Full Idea: Many classical liberals believed that a liberal democracy could function effectively even in the absence of an especially virtuous citizenry, by creating checks and balances. …One set of private interests would check another set of private interests.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: This seems to be the view of those who think a completely free market will evolve into a flourishing and just society. There is a basic debate about the importance of the character of the citizens in any polity. Marxists say they are entangled.
Good citizens need civic virtues of loyalty, independence, diligence, respect, etc. [Kymlicka]
     Full Idea: Galston says responsible citizenship requires four types of civic virtue: general (law-abiding, loyal), social (independent, open-minded), economic (diligent, restrained, adaptable), and political (respect, sensible, judgement, engagement).
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: [Galston's 'Liberal Purposes' 1991] (compressed) This immediately seems to be asking too much, especially for those who know little, or are short of money.
Liberals accept that people need society, but Aristotelians must show that they need political activity [Kymlicka]
     Full Idea: To defend Aristotelian republicanism it is not enough to show that individual require society - liberals do not deny this. They must also show that individuals need to be politically active.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: Interesting. People are not just inactive because they have been rendered powerless. In any group of people there are some who are keen to have a voice, or lead, and others who are largely happy to follow.
Minimal liberal citizenship needs common civility, as well as mere non-interference [Kymlicka]
     Full Idea: Minimal citizenship is often seen as simply requiring non-interference with others, but that ignores a basic requirement of liberal citizenship, which is the social virtue of 'civility' or 'decency'.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: He makes the point that the minimal requirement has to be given up when there is a crisis, which needs much more involvement. This largely describes modern Britain, prior to the Brexit rift.
Modern non-discrimination obliges modern citizens to treat each other as equals [Kymlicka]
     Full Idea: The extension of non-discrimination from government to civil society …involves a radical extension of the obligations of liberal citizenship. The obligation to treat people as equal citizens now applies to everyday decisions.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: This is very difficult for an older generation who felt their 'entitlement' as leading citizens, or who routinely favoured their local traditional community. But they just have to 'get over it'!
The right wing sees citizenship in terms of responsibility to earn a living, rather than rights [Kymlicka]
     Full Idea: According to the New Right, to promote active citizenship-for-all or entitlements, we must focus instead on people's responsibility to earn a living.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: Every creature has to earn a living, but one method is to successfully sponge off others. A cushy job is a sort of sponging. An excessively well paid job is a sort of sponging. Citizenship must involve responsibilities of some sort.
24. Political Theory / D. Ideologies / 5. Democracy / a. Nature of democracy
Modern democratic theory focuses on talk, not votes, because we need consensus or compromise [Kymlicka]
     Full Idea: Modern discussion has shifted from 'vote-centric' (or 'aggregative') to 'talk-centric' democracy. The vote-centric model has no mechanism for developing a consensus, or shaping public opinion, or even formulating an honourable compromise.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: I'm struck by the fact that a person's preferences betweent these two is a reflection of character, or basic attitudes to morality. Some people think democratically about their relationships, and others very obviously don't.
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
In a liberal democracy all subjects of authority have a right to determine the authority [Kymlicka]
     Full Idea: A liberal-democratic system is one in which those people who are subject to political authority have a right to participate in determining that authority.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.4)
     A reaction: This applies to immigrants. The most anti-democratic move in recent democracies is the strategy of trying to make it more difficult to vote, perhaps by demanding identification documents, or creating huge queues.
24. Political Theory / D. Ideologies / 6. Liberalism / b. Liberal individualism
We have become attached to private life because that has become greatly enriched [Kymlicka]
     Full Idea: Our attachment to private life, I believe, is the result not (or not only) of the impoverishment of public life, but the enrichment of private life.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 7)
     A reaction: Interesting. Perhaps a sentiment expected more from a university lecturer than from a poorly-paid labourer. Does he mean watching innumerable TV shows instead of having sing-songs in the local pub? Increased leisure is indisputable.
24. Political Theory / D. Ideologies / 6. Liberalism / e. Liberal community
Liberals must avoid an official culture, as well as an official religion [Kymlicka]
     Full Idea: Just as liberalism precludes the establishment of an official religion, so too there cannot be official cultures that have preferred status.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.3)
     A reaction: This becomes tricky in schools, where the old way of teaching national literature and particular types of music has been eroded in modern times. But once wide diversity is allowed there is no single story which can be taught.
Liberals need more than freedom; they must build a nation, through a language and institutions [Kymlicka]
     Full Idea: Liberals need to replace the idea of 'benign neglect', and recognise the central role of nation-building in a democracy. …This means promoting a common language, and equal access to institutions operating in that language.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.3)
     A reaction: 'Benign neglect' is non-interference with citizens' lives. Obviously the institutions include education, but is a state health service implied? Can equal access by guaranteed to private institutions?
24. Political Theory / D. Ideologies / 6. Liberalism / f. Multiculturalism
Some individuals can gain citizenship as part of a group, rather than as mere individuals [Kymlicka]
     Full Idea: On the view of 'differentiated citizenship', members of certain groups would be incorporated into the community, not only as individuals, but also through the group, and their rights would depend in part on their group membership.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8)
     A reaction: This is obviously a strategy to enable marginalised individuals to be fully included in society. The downside is that individuals gain their social identity through a label, rather than through themselves, which pure liberals dislike. 'Identity politics'.
The status hierarchy is independent of the economic hierarchy [Kymlicka]
     Full Idea: The evidence suggests that (contrary to the Marxist view) the status hierarchy is not reducible to the economic hierarchy.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8)
     A reaction: Kymlicka is particularly thinking of racism, which lowers the status of certain groups, even if they are economically successful. I console myself for my modest economic status by getting lots of education.
Some multiculturalists defended the rights of cohesive minorities against liberal individualism [Kymlicka]
     Full Idea: Defending multiculturalism initially involved endorsing the communitarian critique of liberalism, and viewed minority rights as defending cohesive minority groups against the encroachment of liberal individualism.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.1)
     A reaction: Liberal individualists have to accept these criticisms from Marxists, communitarians and multiculturalists. The lone individual has no group that guarantees support, and individuals (especially the young) can easily sink.
'Culturalist' liberals say that even liberal individuals may need minority rights [Kymlicka]
     Full Idea: The 'liberal culturalist' position is that minorities which share basic liberal principles nonetheless need minority rights.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.2)
     A reaction: Disabled liberals are an obvious example. This strikes me as a promising version of liberalism, which accepts the criticisms of extreme individualism.
Multiculturalism may entail men dominating women in minority groups [Kymlicka]
     Full Idea: Many feminists express concern that multiculturalism in practice typically means giving male members of the group the power to control the women in the group.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.2)
     A reaction: The way the young are treated might also be a problem. The underlying question is whether the minority group is more or less civilised than the central state. Liberalism always fights for the rights of the least powerful.
Liberals must prefer minority right which are freedoms, not restrictions [Kymlicka]
     Full Idea: Liberal defenders of multiculturalism must distinguish 'bad' minority rights which are restrictions from 'good' minority rights which supplement individual rights.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.2)
     A reaction: Presumably no sensible liberal wants to remove all restrictions, so deeper values must be invoked to justify the mode of approved minority rights. A list of human goods seems needed.
Why shouldn't national minorities have their own right to nation-build? [Kymlicka]
     Full Idea: Why should national minorities not have the same powers of nation-building as the majority?
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.4)
     A reaction: A 'national minority' is marked by a different language, or a different religion, or both. No one doubts the majority's right to nation-build. Some further principle would be needed to deny that right to a minority. Maybe the minority was there first?
Multiculturalism is liberal if it challenges inequality, conservative if it emphasises common good [Kymlicka]
     Full Idea: Liberal multiculturalism challenges status inequalities while preserving individual freedom. …Conservative multiculturalism replaces liberal principles with a communitarian politics of the common good, at least at the local or group level.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8.6)
     A reaction: [compressed] This sounds a bit simplistic. Recent emphasis on 'the common good', in the face of white supremacists etc., seems admirable, but surely challenging inequalities promotes the common good? Minority cultures are often conservative.
25. Social Practice / C. Rights / 1. Basis of Rights
Rights are a part of nation-building, to build a common national identity and culture [Kymlicka]
     Full Idea: Extending citizenship to include common social rights was a tool of nation-building, intended in part to construct and consolidate a sense of common national identity and culture.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8)
     A reaction: Kymlicka explains a lot of politics and society in terms of the desire of governments to 'build' their nation. You have to make people who are essentially powerless feel that they are at least in some way involved, and benefiting.
Rights derived from group membership are opposed to the idea of state citizenship [Kymlicka]
     Full Idea: The organisation of society on the basis of rights or claims that derive from group membership is sharply opposed to the concept of society based on citizenship.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8)
     A reaction: [from John Porter 1987] Does this imply that you might have rights as part of a group which you don't have as a state citizen? Positive discrimination, for example. Differential rights sounds like potential trouble.
25. Social Practice / E. Policies / 3. Welfare provision
The welfare state helps to integrate the working classes into a national culture [Kymlicka]
     Full Idea: The development of the welfare state has been quite successful in integrating the working classes into national cultures throughout the Western democracies.
     From: Will Kymlicka (Contemporary Political Philosophy (2nd edn) [2002], 8)
     A reaction: Hard-line capitalists tend to hate the welfare state, as unfair to high earners, but it not only makes workers feel involved, but also provides a healthier, happier, more knowledgeable work force for employers.
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]
     Full Idea: Cantor proved that one-dimensional space has exactly the same number of points as does two dimensions, or our familiar three-dimensional space.
     From: report of George Cantor (works [1880]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.14
27. Natural Reality / D. Time / 1. Nature of Time / c. Idealist time
Maybe time is an extension of the mind [Augustine]
     Full Idea: I begin to wonder whether time is an extension of the mind itself.
     From: Augustine (Confessions [c.398], XI.26)
     A reaction: The observation that the mind creates a 'specious present' (spreading experience out over a short fraction of second) reinforces this. Personally I like David Marshall's proposal that consciousness is entirely memory, which would deny this idea.
To be aware of time it can only exist in the mind, as memory or anticipation [Augustine, by Bardon]
     Full Idea: Augustine answers that for us to be aware of time it must exist only in the mind, …and the difference between past and future is just the difference between memory and anticipation.
     From: report of Augustine (Confessions [c.398]) by Adrian Bardon - Brief History of the Philosophy of Time 1 'Augustine's'
     A reaction: This is an extreme idealist view. Are we to say that the past consists only of what can be remembered, and the future only of what is anticipated? Absurd anti-realism, in my view. Where do his concepts come from, asks Le Poidevin.
27. Natural Reality / D. Time / 1. Nature of Time / g. Growing block
How can ten days ahead be a short time, if it doesn't exist? [Augustine]
     Full Idea: A short time ago or a short time ahead we might put at ten days, but how can anything which does not exist be either long or short?
     From: Augustine (Confessions [c.398], XI.15)
     A reaction: A nice question, which gets at the paradoxical nature of time very nicely. How can it be long, but non-existent? We could break the paradox by concluding '..and therefore time does exist', even though we can't see how.
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
If the past is no longer, and the future is not yet, how can they exist? [Augustine]
     Full Idea: Of the three divisions of time, how can two, the past and the future, be, when the past no longer is, and the future is not yet?
     From: Augustine (Confessions [c.398], XI.14)
     A reaction: This is the oldest bewilderment about time, which naturally leads us to the thought that time cannot actually 'exist'. The remark implies that at least 'now' is safe, but that also succumbs to paradox pretty quickly.
27. Natural Reality / D. Time / 1. Nature of Time / i. Denying time
The whole of the current year is not present, so how can it exist? [Augustine]
     Full Idea: We cannot say that the whole of the current year is present, and if the whole of it is not present, the year is not present.
     From: Augustine (Confessions [c.398], XI.15)
     A reaction: Another nice way of presenting the paradox of time. We are in a particular year, so it has to be real.
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
I know what time is, until someone asks me to explain it [Augustine]
     Full Idea: I know well enough what time is, provided that nobody asks me; but if I am asked what it is and try to explain, I am baffled.
     From: Augustine (Confessions [c.398], XI.14)
     A reaction: A justly famous remark, even though it adds nothing to our knowledge of time. This sort of thought pushes us towards accepting many things as axiomatic, such as time, space, identity, persons, mind.
27. Natural Reality / D. Time / 2. Passage of Time / h. Change in time
I disagree with the idea that time is nothing but cosmic movement [Augustine]
     Full Idea: I once heard a learned man say that time is nothing but the movement of the sun and the moon and the stars, but I do not agree.
     From: Augustine (Confessions [c.398], XI.22)
     A reaction: It is tempting to say that you either take time or movement as axiomatic, and describe one in terms of the other, but you are stuck unable to give the initial statement of the axiom without mentioning the second property you were saving for later.
27. Natural Reality / E. Cosmology / 3. The Beginning
Heaven and earth must be created, because they are subject to change [Augustine]
     Full Idea: The fact that heaven and earth are there proclaims that they were created, for they are subject to change and variation; ..the meaning of change and variation is that something is there which was not there before.
     From: Augustine (Confessions [c.398], XI.04)
     A reaction: It seems possible that the underlying matter is eternal (as in various conservation laws, such as that of energy), and that all change is in the form rather than the substance.
28. God / A. Divine Nature / 2. Divine Nature
Only God is absolutely infinite [Cantor, by Hart,WD]
     Full Idea: Cantor said that only God is absolutely infinite.
     From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1
     A reaction: We are used to the austere 'God of the philosophers', but this gives us an even more austere 'God of the mathematicians'.
28. God / A. Divine Nature / 5. God and Time
If God existed before creation, why would a perfect being desire to change things? [Augustine, by Bardon]
     Full Idea: If nothing existed by God before creation, then what could have happened to, or within, God that led God to decide to create the universe at that particular moment? Why would an eternal or perfect being want or need to change?
     From: report of Augustine (Confessions [c.398]) by Adrian Bardon - Brief History of the Philosophy of Time 1 'Augustine's'
     A reaction: I suppose you could reply that change is superior to stasis, but then why did God delay the creation?
If God is outside time in eternity, can He hear prayers? [Augustine]
     Full Idea: O Lord, since you are outside time in eternity, are you unaware of the things that I tell you?
     From: Augustine (Confessions [c.398], XI.01)
     A reaction: This strikes me as the single most difficult and most elusive question about the nature of a supreme divine being. If the being is trapped in time, as we are, it is greatly diminished, and if it is outside, it is hard to see how it could be a participant.