Combining Texts

All the ideas for 'Defending the Axioms', 'Introduction to the Philosophy of History' and 'Reference and Contingency'

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17 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / d. Nineteenth century philosophy
Hegel inserted society and history between the God-world, man-nature, man-being binary pairs [Hegel, by Safranski]
     Full Idea: Before Hegel, people thought in binary oppositions of God and the world, man and nature, man and being. After Hegel an intervening world of society and history was inserted between these pairs.
     From: report of Georg W.F.Hegel (Introduction to the Philosophy of History [1840]) by Rüdiger Safranski - Nietzsche: a philosophical biography 05
     A reaction: This is what Popper later called 'World Three'. This might be seen as the start of what we islanders call 'continental' philosophy, which we have largely ignored. Analytic philosophy only discovered this through philosophy of language.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice paradoxically allows decomposing a sphere into two identical spheres [Maddy]
     Full Idea: One feature of the Axiom of Choice that troubled many mathematicians was the so-called Banach-Tarski paradox: using the Axiom, a sphere can be decomposed into finitely many parts and those parts reassembled into two spheres the same size as the original.
     From: Penelope Maddy (Defending the Axioms [2011], 1.3)
     A reaction: (The key is that the parts are non-measurable). To an outsider it is puzzling that the Axiom has been universally accepted, even though it produces such a result. Someone can explain that, I'm sure.
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Critics of if-thenism say that not all starting points, even consistent ones, are worth studying [Maddy]
     Full Idea: If-thenism denies that mathematics is in the business of discovering truths about abstracta. ...[their opponents] obviously don't regard any starting point, even a consistent one, as equally worthy of investigation.
     From: Penelope Maddy (Defending the Axioms [2011], 3.3)
     A reaction: I have some sympathy with if-thenism, in that you can obviously study the implications of any 'if' you like, but deep down I agree with the critics.
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Hilbert's geometry and Dedekind's real numbers were role models for axiomatization [Maddy]
     Full Idea: At the end of the nineteenth century there was a renewed emphasis on rigor, the central tool of which was axiomatization, along the lines of Hilbert's axioms for geometry and Dedekind's axioms for real numbers.
     From: Penelope Maddy (Defending the Axioms [2011], 1.3)
If two mathematical themes coincide, that suggest a single deep truth [Maddy]
     Full Idea: The fact that two apparently fruitful mathematical themes turn out to coincide makes it all the more likely that they're tracking a genuine strain of mathematical depth.
     From: Penelope Maddy (Defending the Axioms [2011], 5.3ii)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
Every infinite set of reals is either countable or of the same size as the full set of reals [Maddy]
     Full Idea: One form of the Continuum Hypothesis is the claim that every infinite set of reals is either countable or of the same size as the full set of reals.
     From: Penelope Maddy (Defending the Axioms [2011], 2.4 n40)
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set-theory tracks the contours of mathematical depth and fruitfulness [Maddy]
     Full Idea: Our set-theoretic methods track the underlying contours of mathematical depth. ...What sets are, most fundamentally, is markers for these contours ...they are maximally effective trackers of certain trains of mathematical fruitfulness.
     From: Penelope Maddy (Defending the Axioms [2011], 3.4)
     A reaction: This seems to make it more like a map of mathematics than the actual essence of mathematics.
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
The connection of arithmetic to perception has been idealised away in modern infinitary mathematics [Maddy]
     Full Idea: Ordinary perceptual cognition is most likely involved in our grasp of elementary arithmetic, but ...this connection to the physical world has long since been idealized away in the infinitary structures of contemporary pure mathematics.
     From: Penelope Maddy (Defending the Axioms [2011], 2.3)
     A reaction: Despite this, Maddy's quest is for a 'naturalistic' account of mathematics. She ends up defending 'objectivity' (and invoking Tyler Burge), rather than even modest realism. You can't 'idealise away' the counting of objects. I blame Cantor.
10. Modality / B. Possibility / 5. Contingency
'Superficial' contingency: false in some world; 'Deep' contingency: no obvious verification [Evans, by Macià/Garcia-Carpentiro]
     Full Idea: Evans says intuitively a sentence is 'superficially' contingent if the function from worlds to truth values assigns F to some world; it is 'deeply' contingent if understanding it does not guarantee that there is a verifying state of affairs.
     From: report of Gareth Evans (Reference and Contingency [1979]) by Macià/Garcia-Carpentiro - Introduction to 'Two-Dimensional Semantics' 2
     A reaction: This distinction is used by Davies and Humberstone (1980) to construct an early version of 2-D semantics (see under Language|Semantics). The point is that part comes from understanding it, and another part from assigning truth values.
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Rigid designators can be meaningful even if empty [Evans, by Mackie,P]
     Full Idea: Evans argues that there can be rigid designators that are meaningful even if empty.
     From: report of Gareth Evans (Reference and Contingency [1979]) by Penelope Mackie - How Things Might Have Been 1.8
22. Metaethics / C. The Good / 2. Happiness / a. Nature of happiness
World history has no room for happiness [Hegel]
     Full Idea: World history is not the place for happiness. Periods of happiness are empty pages in history.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: Clearly, Hegel thinks the progress of world history is much more important than happiness. This idea gives backing to those who don't care much about the casualties on either side in a major war.
24. Political Theory / A. Basis of a State / 1. A People / b. The natural life
The state of nature is one of untamed brutality [Hegel]
     Full Idea: The 'state of nature' is not an ideal condition, but a condition of injustice, of violence, of untamed natural drives, inhuman acts and emotions.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: He agrees with Hobbes, and disagrees with Rousseau. Hobbes's solution is authoritarian monarchy, but Hegel's solution is the unified and focused state, in which freedom can be realised.
24. Political Theory / A. Basis of a State / 1. A People / c. A unified people
The soul of the people is an organisation of its members which produces an essential unity [Hegel]
     Full Idea: The soul [of the people] exists only insofar as it is an organisation of its members, which - by taking itself together in its simple unity - produce the soul. Thus the people is one individuality in its essence.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: Hegel is seen (e.g. by Charles Taylor) as the ancestor of a rather attractive communitarianism, but I think Popper is more accurate in seeing him as the first stage of modern totalitarianism. The people seen as one individual terrifies me.
24. Political Theory / D. Ideologies / 6. Liberalism / g. Liberalism critique
The human race matters, and individuals have little importance [Hegel]
     Full Idea: Individuals are of slight importance compared to the mass of the human race.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: A perfect statement of the anti-liberal viewpoint. Hegel is complex, but this is the strand that leads to ridiculous totalitarianism, where the highest ideal is to die for the glory of your nation. Importance can only start from individuals.
24. Political Theory / D. Ideologies / 14. Nationalism
In a good state the goal of the citizens and of the whole state are united [Hegel]
     Full Idea: A state is well constituted and internally strong if the private interest of the citizens is united in the universal goal of the state.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: The obvious question is who decides on the goals, and what to do with the citizens who don't accept them.
25. Social Practice / A. Freedoms / 5. Freedom of lifestyle
The goal of the world is Spirit's consciousness and enactment of freedom [Hegel]
     Full Idea: The final goal of the world is Spirit's consciousness of its freedom, and hence also the actualisation of that very freedom.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 3)
     A reaction: I have the impression that this ridiculous idea has been very influential in modern French philosophy, since they all seem to be dreaming of some perfect freedom at the end of the rainbow. Freedom is good, but this gives it a bad name.
25. Social Practice / E. Policies / 5. Education / d. Study of history
We should all agree that there is reason in history [Hegel]
     Full Idea: We ought to have the firm and unconquerable belief that there is reason in history.
     From: Georg W.F.Hegel (Introduction to the Philosophy of History [1840], 2)
     A reaction: This is a ridiculous but hugely influential idea, and I have no idea what makes Hegel believe it. It is the Stoic idea that nature is intrinsically rational, but extending it to human history is absurd. Human exceptionalism. Needs a dose of Darwin.