Combining Texts

All the ideas for 'fragments/reports', 'The Concept of Law' and 'On the Infinite'

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14 ideas

6. Mathematics / A. Nature of Mathematics / 1. Mathematics
We believe all mathematical problems are solvable [Hilbert]
     Full Idea: The thesis that every mathematical problem is solvable - we are all convinced that it really is so.
     From: David Hilbert (On the Infinite [1925], p.200)
     A reaction: This will include, for example, Goldbach's Conjecture (every even is the sum of two primes), which is utterly simple but with no proof anywhere in sight.
I aim to establish certainty for mathematical methods [Hilbert]
     Full Idea: The goal of my theory is to establish once and for all the certitude of mathematical methods.
     From: David Hilbert (On the Infinite [1925], p.184)
     A reaction: This is the clearest statement of the famous Hilbert Programme, which is said to have been brought to an abrupt end by Gödel's Incompleteness Theorems.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
No one shall drive us out of the paradise the Cantor has created for us [Hilbert]
     Full Idea: No one shall drive us out of the paradise the Cantor has created for us.
     From: David Hilbert (On the Infinite [1925], p.191), quoted by James Robert Brown - Philosophy of Mathematics
     A reaction: This is Hilbert's famous refusal to accept any account of mathematics, such as Kant's, which excludes actual infinities. Cantor had laid out a whole glorious hierarchy of different infinities.
We extend finite statements with ideal ones, in order to preserve our logic [Hilbert]
     Full Idea: To preserve the simple formal rules of ordinary Aristotelian logic, we must supplement the finitary statements with ideal statements.
     From: David Hilbert (On the Infinite [1925], p.195)
     A reaction: I find very appealing the picture of mathematics as rooted in the physical world, and then gradually extended by a series of 'idealisations', which should perhaps be thought of as fictions.
Only the finite can bring certainty to the infinite [Hilbert]
     Full Idea: Operating with the infinite can be made certain only by the finitary.
     From: David Hilbert (On the Infinite [1925], p.201)
     A reaction: See 'Compactness' for one aspect of this claim. I think Hilbert was fighting a rearguard action, and his idea now has few followers.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
The idea of an infinite totality is an illusion [Hilbert]
     Full Idea: Just as in the limit processes of the infinitesimal calculus, the infinitely large and small proved to be a mere figure of speech, so too we must realise that the infinite in the sense of an infinite totality, used in deductive methods, is an illusion.
     From: David Hilbert (On the Infinite [1925], p.184)
     A reaction: This is a very authoritative rearguard action. I no longer think the dispute matters much, it being just a dispute over a proposed new meaning for the word 'number'.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / j. Infinite divisibility
There is no continuum in reality to realise the infinitely small [Hilbert]
     Full Idea: A homogeneous continuum which admits of the sort of divisibility needed to realise the infinitely small is nowhere to be found in reality.
     From: David Hilbert (On the Infinite [1925], p.186)
     A reaction: He makes this remark as a response to Planck's new quantum theory (the year before the big works of Heisenberg and Schrödinger). Personally I don't see why infinities should depend on the physical world, since they are imaginary.
6. Mathematics / C. Sources of Mathematics / 7. Formalism
The subject matter of mathematics is immediate and clear concrete symbols [Hilbert]
     Full Idea: The subject matter of mathematics is the concrete symbols themselves whose structure is immediately clear and recognisable.
     From: David Hilbert (On the Infinite [1925], p.192)
     A reaction: I don't think many people will agree with Hilbert here. Does he mean token-symbols or type-symbols? You can do maths in your head, or with different symbols. If type-symbols, you have to explain what a type is.
6. Mathematics / C. Sources of Mathematics / 8. Finitism
Mathematics divides in two: meaningful finitary statements, and empty idealised statements [Hilbert]
     Full Idea: We can conceive mathematics to be a stock of two kinds of formulas: first, those to which the meaningful communications of finitary statements correspond; and secondly, other formulas which signify nothing and which are ideal structures of our theory.
     From: David Hilbert (On the Infinite [1925], p.196), quoted by David Bostock - Philosophy of Mathematics 6.1
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
My theory aims at the certitude of mathematical methods [Hilbert]
     Full Idea: The goal of my theory is to establish once and for all the certitude of mathematical methods.
     From: David Hilbert (On the Infinite [1925], p.184), quoted by James Robert Brown - Philosophy of Mathematics Ch.5
     A reaction: This dream is famous for being shattered by Gödel's Incompleteness Theorem a mere six years later. Neverless there seem to be more limited certainties which are accepted in mathematics. The certainty of the whole of arithmetic is beyond us.
13. Knowledge Criteria / E. Relativism / 2. Knowledge as Convention
By nature people are close to one another, but culture drives them apart [Hippias]
     Full Idea: I regard you all as relatives - by nature, not by convention. By nature like is akin to like, but convention is a tyrant over humankind and often constrains people to act contrary to nature.
     From: Hippias (fragments/reports [c.430 BCE]), quoted by Plato - Protagoras 337c8
25. Social Practice / C. Rights / 1. Basis of Rights
Hart (against Bentham) says human rights are what motivate legal rights [Hart,HLA, by Sen]
     Full Idea: Whereas Bentham saw rights as a 'child of law', Herbert Hart's view takes the form of seeing human rights as, in effect, 'parents of law'; they motivate specific legislations.
     From: report of H.L.A. Hart (The Concept of Law [1961]) by Amartya Sen - The Idea of Justice 17 'Ethics'
     A reaction: [He cites Hart 1955 'Are there any natural rights?'] I agree with Hart. It is clearer if the parents of law are not referred to as 'rights'. You can demand a right, but it is only a right when it is awarded to you.
25. Social Practice / D. Justice / 2. The Law / a. Legal system
Positive law needs secondary 'rules of recognition' for their correct application [Hart,HLA, by Zimmermann,J]
     Full Idea: Hart says we have secondary legal 'rules of recognition', by which primary positive law is recognised and applied in a regulated manner.
     From: report of H.L.A. Hart (The Concept of Law [1961]) by Jens Zimmermann - Hermeneutics: a very short introduction 6 'Rules'
     A reaction: The example of the authority of a particular court is given.
25. Social Practice / D. Justice / 2. The Law / d. Legal positivism
Hart replaced positivism with the democratic requirement of the people's acceptance [Hart,HLA, by Zimmermann,J]
     Full Idea: Hart replaced Austin's concept of positive law as sovereign command with a more democratic ideal. In modern law-based societies the authority of law depends on the people's acceptance of a law's enduring validity.
     From: report of H.L.A. Hart (The Concept of Law [1961]) by Jens Zimmermann - Hermeneutics: a very short introduction 6 'Hart'
     A reaction: Presumably the ancestor of this view is the social contract of Hobbes and Locke.