9 ideas
16030 | 'Nominal' definitions identify things, but fail to give their essence [Jones,J-E] |
Full Idea: In the Aristotelian tradition, a 'nominal' definition is a pseudo-definition that identifies the members of the species or genus, but fails to capture the essence, e.g. 'man is the featherless biped'. | |
From: Jan-Erik Jones (Real Essence [2012], §2) | |
A reaction: You can 'individuate' an object as 'the only object in that drawer', while revealing nothing about it. So what must a definition do, in addition to picking something out uniquely? |
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) |
23405 | Rituals escape natural chaos, and benefit everyone, by reshaping our motivations [Xunzi (Xun Kuang), by Norden] |
Full Idea: For Xunzi, everyone is better off with rituals …because they allow us to escape the chaotic state of nature. They do not merely set rules for entitlement, though. They are effective because they reshape human motivation. | |
From: report of Xunzi (Xun Kuang) (The Xunzi [c.250 BCE]) by Bryan van Norden - Intro to Classical Chinese Philosophy 10.2 | |
A reaction: Rituals are a basic part of Confucianist thinking, and may be puzzling to outsiders. At there worst rituals are brain-washing, but teaching children good manners is a sort of ritual, meant to channel feelings in a healthy direction |
23406 | Rituals don't arise from human nature; they are the deliberate creations of a sage [Xunzi (Xun Kuang)] |
Full Idea: Rituals and standards of righteousness and proper models and measures are produced from the deliberate efforts of the sage; they are not produced from people's nature. | |
From: Xunzi (Xun Kuang) (The Xunzi [c.250 BCE], 23), quoted by Bryan van Norden - Intro to Classical Chinese Philosophy 10.III | |
A reaction: This is not to say that the sage is not in tune with nature. Human nature is often seen as a sprouting seed, which needs careful husbandry to bring out its best. |