Combining Texts

All the ideas for 'works', 'Symbolic Reasoning' and 'Logicism, Some Considerations (PhD)'

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9 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The null class is the class with all the non-existents as its members [MacColl, by Lackey]
     Full Idea: In 1905 the Scottish logician Hugh MacColl published a paper in which he argued that the null class in logic should be taken as the class with all the non-existents as its members.
     From: report of Hugh MacColl (Symbolic Reasoning [1905]) by Douglas Lackey - Intros to Russell's 'Essays in Analysis' p.95
     A reaction: For the null object (zero) Frege just chose one sample concept with an empty extension. MacColl's set seems to have a lot of members, given that it is 'null'. How many, I wonder? Russell responded to this paper.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
Obtaining numbers by abstraction is impossible - there are too many; only a rule could give them, in order [Benacerraf]
     Full Idea: Not all numbers could possibly have been learned à la Frege-Russell, because we could not have performed that many distinct acts of abstraction. Somewhere along the line a rule had to come in to enable us to obtain more numbers, in the natural order.
     From: Paul Benacerraf (Logicism, Some Considerations (PhD) [1960], p.165)
     A reaction: Follows on from Idea 13411. I'm not sure how Russell would deal with this, though I am sure his account cannot be swept aside this easily. Nevertheless this seems powerful and convincing, approaching the problem through the epistemology.
We must explain how we know so many numbers, and recognise ones we haven't met before [Benacerraf]
     Full Idea: Both ordinalists and cardinalists, to account for our number words, have to account for the fact that we know so many of them, and that we can 'recognize' numbers which we've neither seen nor heard.
     From: Paul Benacerraf (Logicism, Some Considerations (PhD) [1960], p.166)
     A reaction: This seems an important contraint on any attempt to explain numbers. Benacerraf is an incipient structuralist, and here presses the importance of rules in our grasp of number. Faced with 42,578,645, we perform an act of deconstruction to grasp it.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
If numbers are basically the cardinals (Frege-Russell view) you could know some numbers in isolation [Benacerraf]
     Full Idea: If we accept the Frege-Russell analysis of number (the natural numbers are the cardinals) as basic and correct, one thing which seems to follow is that one could know, say, three, seventeen, and eight, but no other numbers.
     From: Paul Benacerraf (Logicism, Some Considerations (PhD) [1960], p.164)
     A reaction: It seems possible that someone might only know those numbers, as the patterns of members of three neighbouring families (the only place where they apply number). That said, this is good support for the priority of ordinals. See Idea 13412.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
An adequate account of a number must relate it to its series [Benacerraf]
     Full Idea: No account of an individual number is adequate unless it relates that number to the series of which it is a member.
     From: Paul Benacerraf (Logicism, Some Considerations (PhD) [1960], p.169)
     A reaction: Thus it is not totally implausible to say that 2 is several different numbers or concepts, depending on whether you see it as a natural number, an integer, a rational, or a real. This idea is the beginning of modern structuralism.
15. Nature of Minds / B. Features of Minds / 2. Unconscious Mind
Freud treats the unconscious as intentional and hence mental [Freud, by Searle]
     Full Idea: Freud thinks that our unconscious mental states exist as occurrent intrinsic intentional states even when unconscious. Their ontology is that of the mental, even when they are unconscious.
     From: report of Sigmund Freud (works [1900]) by John Searle - The Rediscovery of the Mind Ch. 7.V
     A reaction: Searle states this view in order to attack it. Whether such states are labelled as 'mental' seems uninteresting. Whether unconscious states can be intentional is crucial, and modern scientific understanding of the brain strongly suggest they can.
16. Persons / C. Self-Awareness / 3. Limits of Introspection
Freud and others have shown that we don't know our own beliefs, feelings, motive and attitudes [Freud, by Shoemaker]
     Full Idea: Freud persuaded many that beliefs, wishes and feelings are sometimes unconscious, and even sceptics about Freud acknowledge that there is self-deception about motive and attitudes.
     From: report of Sigmund Freud (works [1900]) by Sydney Shoemaker - Introspection p.396
     A reaction: This seems to me obviously correct. The traditional notion is that the consciousness is the mind, but now it seems obvious that consciousness is only one part of the mind, and maybe even a peripheral (epiphenomenal) part of it.
18. Thought / A. Modes of Thought / 3. Emotions / a. Nature of emotions
Freud said passions are pressures of some flowing hydraulic quantity [Freud, by Solomon]
     Full Idea: Freud argued that the passions in general …were the pressures of a yet unknown 'quantity' (which he simply designated 'Q'). He first thought this flowed through neurones, …and always couched the idea in the language of hydraulics.
     From: report of Sigmund Freud (works [1900]) by Robert C. Solomon - The Passions 3.4
     A reaction: This is the main target of Solomon's criticism, because its imagery has become so widespread. It leads to talk of suppressing emotions, or sublimating them. However, it is not too different from Nietzsche's 'drives' or 'will to power'.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Freud is pessimistic about human nature; it is ambivalent motive and fantasy, rather than reason [Freud, by Murdoch]
     Full Idea: Freud takes a thoroughly pessimistic view of human nature. ...Introspection reveals only the deep tissue of ambivalent motive, and fantasy is a stronger force than reason. Objectivity and unselfishness are not natural to human beings.
     From: report of Sigmund Freud (works [1900], II) by Iris Murdoch - The Sovereignty of Good II
     A reaction: Interesting. His view seems to have coloured the whole of modern culture, reinforced by the hideous irrationality of the Nazis. Adorno and Horkheimer attacking the Enlightenment was the last step in that process.