13 ideas
13445 | Descartes showed a one-one order-preserving match between points on a line and the real numbers [Descartes, by Hart,WD] |
Full Idea: Descartes founded analytic geometry on the assumption that there is a one-one order-preserving correspondence between the points on a line and the real numbers. | |
From: report of René Descartes (works [1643]) by William D. Hart - The Evolution of Logic 1 |
16774 | Descartes thinks distinguishing substances from aggregates is pointless [Descartes, by Pasnau] |
Full Idea: Descartes thinks it is a pointless relic of scholastic metaphysics to dispute over the boundaries between substances and mere aggregates. | |
From: report of René Descartes (works [1643]) by Robert Pasnau - Metaphysical Themes 1274-1671 25.6 | |
A reaction: This is Pasnau's carefully considered conclusion, with which others may not agree. It presumably captures the attitude of modern science generally to such issues. |
13952 | Essentialism says some of a thing's properties are necessary, and could not be absent [Cartwright,R] |
Full Idea: Essentialism, as I shall understand it, is the doctrine that among the attributes of a thing some are essential, others merely accidental. Its essential attributes are those it has necessarily, those it could not have lacked. | |
From: Richard Cartwright (Some Remarks on Essentialism [1968], p.149) | |
A reaction: The problem with this, which Cartwright does not address, is that trivial and gerrymandered properties (such as having self-identity, or being 'such that 2+2=4') seem to be necessarily, but don't seem to constitute the essence of a thing. |
13954 | The difficulty in essentialism is deciding the grounds for rating an attribute as essential [Cartwright,R] |
Full Idea: I see no reason for thinking essentialism unintelligible, but a chief perplexity is the obscurity of the grounds on which ratings of attributes as essential or accidental are to be made. | |
From: Richard Cartwright (Some Remarks on Essentialism [1968], p.158) | |
A reaction: In that case some of us younger philosophers will have to roll up our sleeves and tease out the grounds for essentialism, starting with Aristotle and Leibniz, and ending with the successes of modern science. |
13955 | Essentialism is said to be unintelligible, because relative, if necessary truths are all analytic [Cartwright,R] |
Full Idea: Apparently those who think essentialism unintelligible see support for their position in the doctrine that necessary truths are all analytic. Only relative to some mode of designation does it make sense to speak of an object as necessarily this or that. | |
From: Richard Cartwright (Some Remarks on Essentialism [1968], p.158) | |
A reaction: He has in mind Quine and his mathematician-cyclist (Idea 8482). Personally I have no problems with the example. No one is essentially a cyclist - that isn't what essence is. Two-legged people can be cyclists. |
13953 | An act of ostension doesn't seem to need a 'sort' of thing, even of a very broad kind [Cartwright,R] |
Full Idea: For an ostension to be successful it is surely not necessary that I gather what sort of object it is you have indicated, such as being a horse or a zebra. I may even gather which thing you have indicated without knowing that it is a mammal or even alive. | |
From: Richard Cartwright (Some Remarks on Essentialism [1968], p.157) | |
A reaction: This nicely articulates the objection I have always felt to Geach's relative identity. 'Oh my God, what the hell is THAT???' is probably going to be a successful act of verbal reference, even while explicitly denying all knowledge of sortals. |
7400 | Descartes said images can refer to objects without resembling them (as words do) [Descartes, by Tuck] |
Full Idea: Descartes argued (in 'The World') that just as words refer to objects, but they do not resemble them, in the same way, visual images or other sensory inputs relate to objects without depicting them. | |
From: report of René Descartes (works [1643]) by Richard Tuck - Hobbes | |
A reaction: This strikes me as a rather significant and plausible claim, which might contain the germ of the idea of a language of thought. It is also the basis for the recent view that language is the best route to understanding the mind. |
4310 | We have inner awareness of our freedom [Descartes] |
Full Idea: We have inner awareness of our freedom. | |
From: René Descartes (works [1643]) | |
A reaction: This begs a few questions. I may be directly aware that I have not been hypnotised, but no one would accept it as proof. |
6553 | Descartes discussed the interaction problem, and compared it with gravity [Descartes, by Lycan] |
Full Idea: Descartes himself was well aware of the interaction problem, and corresponded uncomfortably with Princess Elizabeth on the matter; …he pointed out that gravity is causal despite not being a physical object. | |
From: report of René Descartes (works [1643]) by William Lycan - Consciousness n1.3 | |
A reaction: Lycan observes that at least gravity is in space-time, unlike the Cartesian mind. Pierre Gassendi had pointed out the problem to Descartes in the Fifth Objection to the 'Meditations' (see Idea 3400). |
7861 | Libet says the processes initiated in the cortex can still be consciously changed [Libet, by Papineau] |
Full Idea: Libet himself points out that the conscious decisions still have the power to 'endorse' or 'cancel', so to speak, the processes initiated by the earlier cortical activity: no action will result if the action's execution is consciously countermanded. | |
From: report of Benjamin Libet (Unconscious Cerebral Initiative [1985]) by David Papineau - Thinking about Consciousness 1.4 | |
A reaction: This is why Libet's findings do not imply 'epiphenomenalism'. It seems that part of a decisive action is non-conscious, undermining the all-or-nothing view of consciousness. Searle tries to smuggle in free will at this point (Idea 3817). |
6660 | Libet found conscious choice 0.2 secs before movement, well after unconscious 'readiness potential' [Libet, by Lowe] |
Full Idea: Libet found that a subject's conscious choice to move was about a fifth of a second before movement, and thus later than the onset of the brain's so-called 'readiness potential', which seems to imply that unconscious processes initiates action. | |
From: report of Benjamin Libet (Unconscious Cerebral Initiative [1985]) by E.J. Lowe - Introduction to the Philosophy of Mind Ch.9 | |
A reaction: Of great interest to philosophers! It seems to make conscious choices epiphenomenal. The key move, I think, is to give up the idea of consciousness as being all-or-nothing. My actions are still initiated by 'me', but 'me' shades off into unconsciousness. |
19676 | Nature is devoid of thought [Descartes, by Meillassoux] |
Full Idea: It is Descartes who ratifies the idea that nature is devoid of thought. | |
From: report of René Descartes (works [1643]) by Quentin Meillassoux - After Finitude; the necessity of contingency 5 | |
A reaction: His dualism is crucial, along with his ontological argument, because they make all mentality supernatural. Remember, for Descartes animals are mindless machines. |
6518 | Matter can't just be Descartes's geometry, because a filler of the spaces is needed [Robinson,H on Descartes] |
Full Idea: Notoriously, the Cartesian idea that matter is purely geometrical will not do, for it leaves no distinction between matter and empty volumes: a filler for these volumes is required. | |
From: comment on René Descartes (works [1643]) by Howard Robinson - Perception IX.3 | |
A reaction: Descartes thinks of matter as 'extension'. Descartes's error seems so obvious that it is a puzzle why he made it. He may have confused epistemology and ontology - all we can know of matter is its extension in space. |