10 ideas
17884 | Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner] |
Full Idea: There are many coherent stopping points in the hierarchy of increasingly strong mathematical systems, starting with strict finitism, and moving up through predicativism to the higher reaches of set theory. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], Intro) |
17893 | 'Reflection principles' say the whole truth about sets can't be captured [Koellner] |
Full Idea: Roughly speaking, 'reflection principles' assert that anything true in V [the set hierarchy] falls short of characterising V in that it is true within some earlier level. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 2.1) |
17894 | We have no argument to show a statement is absolutely undecidable [Koellner] |
Full Idea: There is at present no solid argument to the effect that a given statement is absolutely undecidable. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 5.3) |
17890 | There are at least eleven types of large cardinal, of increasing logical strength [Koellner] |
Full Idea: Some of the standard large cardinals (in order of increasing (logical) strength) are: inaccessible, Mahlo, weakly compact, indescribable, Erdös, measurable, strong, Wodin, supercompact, huge etc. (...and ineffable). | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4) | |
A reaction: [I don't understand how cardinals can have 'logical strength', but I pass it on anyway] |
17887 | PA is consistent as far as we can accept, and we expand axioms to overcome limitations [Koellner] |
Full Idea: To the extent that we are justified in accepting Peano Arithmetic we are justified in accepting its consistency, and so we know how to expand the axiom system so as to overcome the limitation [of Gödel's Second Theorem]. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.1) | |
A reaction: Each expansion brings a limitation, but then you can expand again. |
17891 | Arithmetical undecidability is always settled at the next stage up [Koellner] |
Full Idea: The arithmetical instances of undecidability that arise at one stage of the hierarchy are settled at the next. | |
From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4) |
22818 | Liberals are not too individualistic, because people recognise and value social relations [Kymlicka] |
Full Idea: It is alleged that liberals fail to recognise that people are naturally social or communal. …But liberals believe that people form and join social relations in which they come to understand and pursue the good. | |
From: Will Kymlicka (Liberal Individualism and Liberal Neutrality [1989], Conc) | |
A reaction: This is particulary aimed at communitarians, who see liberalism as based on a distorted concept of people as isolated beings. Personally I am beginning to shift my views from Aristotelian communitarianism to modern liberalism, so I like this idea. |
1466 | Claims about God don't seem to claim or deny anything tangible, so evidence is irrelevant [Flew, by PG] |
Full Idea: An assertion is logically equivalent to denying its opposite, but claims about a 'gardener', or God, make neither claims nor denials of anything, so no evidence can count against the claim, or for it. | |
From: report of Antony Flew (Theology and Falsification [1950]) by PG - Db (ideas) |
1465 | You can't claim a patch of land is tended by a 'gardener' if there is no evidence, and all counter-evidence is rejected [Flew, by PG] |
Full Idea: If someone claimed a patch of land was tended by a 'gardener', but there was never a shred of evidence to support this view, the claim would gradually dissolve into meaninglessness, especially if it was suggested that evidence was irrelevant. | |
From: report of Antony Flew (Theology and Falsification [1950]) by PG - Db (ideas) |
1467 | Religious people seem unwilling to accept any evidence that God does not love us, so their claim is unfalsifiable [Flew, by PG] |
Full Idea: Religious people seem unwilling to accept any evidence which shows that God does not love us, so what would they accept? If nothing counts that way, their claim is unfalsifiable, and hence meaningless. | |
From: report of Antony Flew (Theology and Falsification [1950]) by PG - Db (ideas) |