10 ideas
| 17833 | The first-order ZF axiomatisation is highly non-categorical [Hallett,M] |
| Full Idea: The first-order Sermelo-Fraenkel axiomatisation is highly non-categorical. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1213) |
| 17834 | Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M] |
| Full Idea: The non-categoricity of the axioms which Zermelo demonstrates reveals an incompleteness of a sort, ....for this seems to show that there will always be a set (indeed, an unending sequence) that the basic axioms are incapable of revealing to be sets. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1215) | |
| A reaction: Hallett says the incompleteness concerning Zermelo was the (transfinitely) indefinite iterability of the power set operation (which is what drives the 'iterative conception' of sets). |
| 17837 | Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M] |
| Full Idea: Unlike earlier writers (such as Fraenkel), Zermelo clearly allows that there might be ur-elements (that is, objects other than the empty set, which have no members). Indeed he sees in this the possibility of widespread application of set-theory. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
| 17836 | The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M] |
| Full Idea: In 1938, Gödel showed that ZF plus the General Continuum Hypothesis is consistent if ZF is. Cohen showed that ZF and not-GCH is also consistent if ZF is, which finally shows that neither GCH nor ¬GCH can be proved from ZF itself. | |
| From: Michael Hallett (Introduction to Zermelo's 1930 paper [1996], p.1217) |
| 7876 | Even if we identify pain with neural events, we can't explain why those neurons cause that feeling [Levine, by Papineau] |
| Full Idea: Materialists identify pain with the firing of nociceptive-specific neurons in the parietal cortex. Even so, Levine argues, we will still lack any explanation of why nociceptive-specific neurons yield pain. | |
| From: report of Joseph Levine (Purple Haze [2001]) by David Papineau - Thinking about Consciousness 5.1 | |
| A reaction: [Proposed by Levine in 1983] I don't think we need to instantly go dualist when faced with this, but we may all eventually have to concede a bit of mysterianism. The explanation may be holistic (and hence hopelessly complex). |
| 7877 | Only phenomenal states have an explanatory gap; water is fully explained by H2O [Levine, by Papineau] |
| Full Idea: Levine says the explanatory gap is peculiar to phenomenal states. Once water has been identified with H2O, or temperature with mean kinetic energy, we do not continue to ask why H2O yields water, or why mean kinetic energy yields temperature. | |
| From: report of Joseph Levine (Purple Haze [2001]) by David Papineau - Thinking about Consciousness 5.1 | |
| A reaction: Everything is mysterious if you think about if for long enough. What about a representational gap? Why do those neurons represent that tree (if the neurons aren't tree-shaped)? To understand qualia, we must understand the whole brain, I suspect. |
| 7878 | Materialism won't explain phenomenal properties, because the latter aren't seen in causal roles [Papineau on Levine] |
| Full Idea: We cannot give materialist explanations of why brain yields phenomenal properties because phenomenal concepts are not associated with descriptions of causal roles in the same way as pre-theoretical terms in other areas of science. | |
| From: comment on Joseph Levine (Purple Haze [2001]) by David Papineau - Thinking about Consciousness 5.1 | |
| A reaction: I think Papineau has part of the answer, and I certainly like his notion of Conceptual Dualism, but if qualia are physical, there must be a physical account of how they acquire their properties. I think the whole brain needs to be understood first. |
| 7518 | If folk psychology gives a network of causal laws, that fits neatly with functionalism [Churchland,PM] |
| Full Idea: The portrait of folk psychology as a network of causal laws dovetailed neatly with the emerging philosophy of mind called functionalism. | |
| From: Paul M. Churchland (Folk Psychology [1996], II) | |
| A reaction: And from the lower levels functionalism is supported by the notion that the brain is modular. Note the word 'laws'; this implies an underlying precision in folk psychology, which is then easily attacked. Maybe the network is too complex for simple laws. |
| 7519 | Many mental phenomena are totally unexplained by folk psychology [Churchland,PM] |
| Full Idea: Folk psychology fails utterly to explain a considerable variety of central psychological phenomena: mental illness, sleep, creativity, memory, intelligence differences, and many forms of learning, to cite just a few. | |
| From: Paul M. Churchland (Folk Psychology [1996], III) | |
| A reaction: If folk psychology is a theory, it will have been developed to predict behaviour, rather than as a full-blown psychological map. The odd thing is that some people seem to be very bad at folk psychology. |
| 7520 | Folk psychology never makes any progress, and is marginalised by modern science [Churchland,PM] |
| Full Idea: Folk psychology has not progressed significantly in the last 2500 years; if anything, it has been steadily in retreat during this period; it does not integrate with modern science, and its emerging wallflower status bodes ill for its future. | |
| From: Paul M. Churchland (Folk Psychology [1996], III) | |
| A reaction: [compressed] However, while shares in alchemy and astrology have totally collapsed, folk psychology shows not the slightest sign of going away, and it is unclear how it ever could. See Idea 3177. |