Combining Texts

All the ideas for 'Precis of 'Limits of Abstraction'', 'Manuscript remains' and 'Cantorian Abstraction: Recon. and Defence'

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12 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophers can't be religious, and don't need to be; philosophy is perilous but free [Schopenhauer]
     Full Idea: No one who is religious attains to philosophy; he does not need it. No one who really philosophizes is religious; he walks without leading-strings, perilously but free.
     From: Arthur Schopenhauer (Manuscript remains [1855], II p.241-3), quoted by Peter B. Lewis - Schopenhauer 3
     A reaction: This is a direct reply to the opposite view expressed by Schleiermacher (and quoted by Lewis). I would say that to be a philosopher one must give priority to the philosophy, ahead of any religious beliefs. Thinking must be free.
2. Reason / D. Definition / 2. Aims of Definition
Definitions concern how we should speak, not how things are [Fine,K]
     Full Idea: Our concern in giving a definition is not to say how things are by to say how we wish to speak
     From: Kit Fine (Precis of 'Limits of Abstraction' [2005], p.310)
     A reaction: This sounds like an acceptable piece of wisdom which arises out of analytical and linguistic philosophy. It puts a damper on the Socratic dream of using definition of reveal the nature of reality.
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
I think of variables as objects rather than as signs [Fine,K]
     Full Idea: It is natural nowadays to think of variables as a certain kind of sign, but I wish to think of them as a certain kind of object.
     From: Kit Fine (Cantorian Abstraction: Recon. and Defence [1998], §2)
     A reaction: Fine has a theory based on 'arbitrary objects', which is a rather charming idea. The cell of a spreadsheet is a kind of object, I suppose. A variable might be analogous to a point in space, where objects can locate themselves.
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
If Hume's Principle can define numbers, we needn't worry about its truth [Fine,K]
     Full Idea: Neo-Fregeans have thought that Hume's Principle, and the like, might be definitive of number and therefore not subject to the usual epistemological worries over its truth.
     From: Kit Fine (Precis of 'Limits of Abstraction' [2005], p.310)
     A reaction: This seems to be the underlying dream of logicism - that arithmetic is actually brought into existence by definitions, rather than by truths derived from elsewhere. But we must be able to count physical objects, as well as just counting numbers.
Hume's Principle is either adequate for number but fails to define properly, or vice versa [Fine,K]
     Full Idea: The fundamental difficulty facing the neo-Fregean is to either adopt the predicative reading of Hume's Principle, defining numbers, but inadequate, or the impredicative reading, which is adequate, but not really a definition.
     From: Kit Fine (Precis of 'Limits of Abstraction' [2005], p.312)
     A reaction: I'm not sure I understand this, but the general drift is the difficulty of building a system which has been brought into existence just by definition.
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
If green is abstracted from a thing, it is only seen as a type if it is common to many things [Fine,K]
     Full Idea: In traditional abstraction, the colour green merely has the intrinsic property of being green, other properties of things being abstracted away. But why should that be regarded as a type? It must be because the property is common to the instances.
     From: Kit Fine (Cantorian Abstraction: Recon. and Defence [1998], §5)
     A reaction: A nice question which shows that the much-derided single act of abstraction is not sufficient to arrive at a concept, so that abstraction is a more complex matter (perhaps even a rational one) than simple empiricists believe.
18. Thought / E. Abstraction / 2. Abstracta by Selection
To obtain the number 2 by abstraction, we only want to abstract the distinctness of a pair of objects [Fine,K]
     Full Idea: In abstracting from the elements of a doubleton to obtain 2, we do not wish to abstract away from all features of the objects. We wish to take account of the fact that the two objects are distinct; this alone should be preserved under abstraction.
     From: Kit Fine (Cantorian Abstraction: Recon. and Defence [1998], §3)
     A reaction: This is Fine's strategy for meeting Frege's objection to abstraction, summarised in Idea 9146. It seems to use the common sense idea that abstraction is not all-or-nothing. Abstraction has degrees (and levels).
We should define abstraction in general, with number abstraction taken as a special case [Fine,K]
     Full Idea: Number abstraction can be taken to be a special case of abstraction in general, which can then be defined without recourse to the concept of number.
     From: Kit Fine (Cantorian Abstraction: Recon. and Defence [1998], §3)
     A reaction: At last, a mathematical logician recognising that they don't have a monopoly on abstraction. It is perfectly obvious that abstractions of simple daily concepts must be chronologically and logically prior to number abstraction. Number of what?
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
An abstraction principle should not 'inflate', producing more abstractions than objects [Fine,K]
     Full Idea: If an abstraction principle is going to be acceptable, then it should not 'inflate', i.e. it should not result in there being more abstracts than there are objects. By this mark Hume's Principle will be acceptable, but Frege's Law V will not.
     From: Kit Fine (Precis of 'Limits of Abstraction' [2005], p.307)
     A reaction: I take this to be motivated by my own intuition that abstract concepts had better be rooted in the world, or they are not worth the paper they are written on. The underlying idea this sort of abstraction is that it is 'shared' between objects.
18. Thought / E. Abstraction / 8. Abstractionism Critique
After abstraction all numbers seem identical, so only 0 and 1 will exist! [Fine,K]
     Full Idea: In Cantor's abstractionist account there can only be two numbers, 0 and 1. For abs(Socrates) = abs(Plato), since their numbers are the same. So the number of {Socrates,Plato} is {abs(Soc),abs(Plato)}, which is the same number as {Socrates}!
     From: Kit Fine (Cantorian Abstraction: Recon. and Defence [1998], §1)
     A reaction: Fine tries to answer this objection, which arises from §45 of Frege's Grundlagen. Fine summarises that "indistinguishability without identity appears to be impossible". Maybe we should drop talk of numbers in terms of sets.
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
As the subject of willing I am wretched, but absorption in knowledge is bliss [Schopenhauer]
     Full Idea: As the subject of willing I am an exceedingly wretched being, and all our suffering consistd in willing, ...but as soon as I am absorbed in knowledge, I am blissfully happy and nothing can assail me.
     From: Arthur Schopenhauer (Manuscript remains [1855], I p.137), quoted by Peter B. Lewis - Schopenhauer 4
     A reaction: So the source of his pessimism is subjection to his own will. However, since becoming absorbed in knowledge is an easy task for a scholar, he has little to grumble about. Nietzsche mocked the great pessimist for playing the flute every day.
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / b. Rational ethics
To deduce morality from reason is blasphemy, because it is holy, and far above reason [Schopenhauer]
     Full Idea: To deduce from reason [Vernunft] the moral element in conduct is blasphemy. In this element there is expressed the better consciousness which lies far above all reason. expresses itself in conduct as holiness, and is the true salvation of the world.
     From: Arthur Schopenhauer (Manuscript remains [1855], I p.47), quoted by Peter B. Lewis - Schopenhauer 3
     A reaction: Aimed at Kant. Only Plato could inspire a non-religious person to write about morality is such terms. Maybe also the stoic ideal of beautiful deeds (given the supreme value Schopenhauer placed on the arts).