Combining Texts

All the ideas for 'Human Flourishing, Ethics and Liberty', 'What is Cantor's Continuum Problem?' and 'Sentences'

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9 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
We perceive the objects of set theory, just as we perceive with our senses [Gödel]
     Full Idea: We have something like perception of the objects of set theory, shown by the axioms forcing themselves on us as being true. I don't see why we should have less confidence in this kind of perception (i.e. mathematical intuition) than in sense perception.
     From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], p.483), quoted by Michčle Friend - Introducing the Philosophy of Mathematics 2.4
     A reaction: A famous strong expression of realism about the existence of sets. It is remarkable how the ingredients of mathematics spread themselves before the mind like a landscape, inviting journeys - but I think that just shows how minds cope with abstractions.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
Gödel proved the classical relative consistency of the axiom V = L [Gödel, by Putnam]
     Full Idea: Gödel proved the classical relative consistency of the axiom V = L (which implies the axiom of choice and the generalized continuum hypothesis). This established the full independence of the continuum hypothesis from the other axioms.
     From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by Hilary Putnam - Mathematics without Foundations
     A reaction: Gödel initially wanted to make V = L an axiom, but the changed his mind. Maddy has lots to say on the subject.
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / a. Set theory paradoxes
Set-theory paradoxes are no worse than sense deception in physics [Gödel]
     Full Idea: The set-theoretical paradoxes are hardly any more troublesome for mathematics than deceptions of the senses are for physics.
     From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], p.271), quoted by Philip Kitcher - The Nature of Mathematical Knowledge 03.4
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
The Continuum Hypothesis is not inconsistent with the axioms of set theory [Gödel, by Clegg]
     Full Idea: Gödel proved that the Continuum Hypothesis was not inconsistent with the axioms of set theory.
     From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.15
If set theory is consistent, we cannot refute or prove the Continuum Hypothesis [Gödel, by Hart,WD]
     Full Idea: Gödel proved that (if set theory is consistent) we cannot refute the continuum hypothesis, and Cohen proved that (if set theory is consistent) we cannot prove it either.
     From: report of Kurt Gödel (What is Cantor's Continuum Problem? [1964]) by William D. Hart - The Evolution of Logic 10
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Basic mathematics is related to abstract elements of our empirical ideas [Gödel]
     Full Idea: Evidently the 'given' underlying mathematics is closely related to the abstract elements contained in our empirical ideas.
     From: Kurt Gödel (What is Cantor's Continuum Problem? [1964], Suppl)
     A reaction: Yes! The great modern mathematical platonist says something with which I can agree. He goes on to hint at a platonic view of the structure of the empirical world, but we'll let that pass.
22. Metaethics / C. The Good / 1. Goodness / d. Good as virtue
Basing ethics on flourishing makes it consequentialist, as actions are judged by contributing to it [Harman]
     Full Idea: Basing ethics on human flourishing tends towards utilitarianism or consequentialism; actions, character traits, laws, and so on are to be assessed with reference to their contributions to human flourishing.
     From: Gilbert Harman (Human Flourishing, Ethics and Liberty [1983], 9.2.2)
     A reaction: This raises the question of whether only virtue can contribute to flourishing, or whether a bit of vice might be helpful. This problem presumably pushed the Stoics to say that virtue itself is the good, rather than the resulting flourishing.
22. Metaethics / C. The Good / 2. Happiness / b. Eudaimonia
What counts as 'flourishing' must be relative to various sets of values [Harman]
     Full Idea: If we base our ethics on human flourishing, one implication would seem to be moral relativism, since what counts as 'flourishing' seems inevitably relative to one or other set of values.
     From: Gilbert Harman (Human Flourishing, Ethics and Liberty [1983], 9.2.1)
     A reaction: This remark seems to make the relativist assumption that all value systems are equal. For Aristotle, flourishing is no more relative than health is. No one can assert that illness has an intrinsically high value in human life.
29. Religion / B. Monotheistic Religion / 4. Christianity / d. Heresy
Heretics should be eradicated like wolves [Aquinas]
     Full Idea: Heretics are wolves …and therefore ought to be eradicated.
     From: Thomas Aquinas (Sentences [1264], IV.13.2.3sc), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 20.2