8 ideas
15453 | The main rivals to universals are resemblance or natural-class nominalism, or sparse trope theory [Lewis] |
Full Idea: The leading rivals to a theory of universals are resemblance or natural-class nominalism, or sparse trope theory. | |
From: David Lewis (Comment on Armstrong and Forrest [1986], p.110) | |
A reaction: If that is the complete menu, I choose resemblance nominalism. All discussion of properties in terms of classes is wildly misguided (because properties come first). Why not 'natural' tropes? |
15452 | We could not uphold a truthmaker for 'Fa' without structures [Lewis] |
Full Idea: We could not, without structures, uphold the principle that every truth has a truthmaker. If Fa is true, the truthmaker is not F, not a, nor both together; not their mereological sum; not a set-theoretic construction. These would exist just the same. | |
From: David Lewis (Comment on Armstrong and Forrest [1986], p.109) | |
A reaction: This point ought to trouble Lewis, as well as Armstrong and Forrest. If we assert 'Fa', we must (in any theory) have some idea of what unites them, as well as of their separate existence. It must a fact about 'a', not a fact about 'F'. |
22593 | Our sensation of light may not be the same as what produces the sensation [Descartes] |
Full Idea: There can be a difference between our sensation of light and what is in the objects that produce that sensation in us. | |
From: René Descartes (The World [1631]), quoted by Ian Dunt - How to be a Liberal 1 | |
A reaction: Note only that they 'may' differ, and that he does not assert that they are entirely different. Secondary qualities give information, and are not just mental events. |
4894 | I say Mary does not have new knowledge, but knows an old fact in a new way [Perry on Jackson] |
Full Idea: I say Mary knows an old fact in a new way, but I do not find a new bit of knowledge and a new fact. | |
From: comment on Frank Jackson (What Mary Didn't Know [1986]) by John Perry - Knowledge, Possibility and Consciousness §7.3 | |
A reaction: This seems roughly the right way to attack Jackson's 'knowledge argument', by asking exactly what he means by 'knowledge'. It is hard to see how 'qualia' can be both the means of acquiring knowledge, and the thing itself. |
4895 | Is it unfair that physicalist knowledge can be written down, but dualist knowledge can't be [Perry on Jackson] |
Full Idea: Jackson seems to imply that it isn't fair that all physicalist knowledge can be written down, but not all dualist knowledge can be. | |
From: comment on Frank Jackson (What Mary Didn't Know [1986]) by John Perry - Knowledge, Possibility and Consciousness §7.5 | |
A reaction: This pinpoints a problem for the 'Mary' example - that Mary's new sight of colour is claimed as 'knowledge', and yet the whole point is that it cannot be expressed in propositions (which seems to leave it as 'procedural' or 'acquaintance' knowledge). |
4886 | Mary knows all the physical facts of seeing red, but experiencing it is new knowledge [Jackson] |
Full Idea: Mary knows all the physical facts. ..It seems, however, that Mary does not know all there is to know. For when she is let out of the black and white room .. she will learn what it is like to see something red. | |
From: Frank Jackson (What Mary Didn't Know [1986], §1.4) | |
A reaction: Jackson is begging the question. A new physical event occurs when the red wavelength stimulates Mary's visual cortex for the first time. For an empiricist raw experience creates knowledge, so it can't BE knowledge. Does Mary acquire a new concept? |
16569 | The Hot, Cold, Wet and Dry of the philosophers need themselves to be explained [Descartes] |
Full Idea: If you find it strange that in explaining these elements I do not use the qualities called Hot, Cold, Wet and Dry - as the philosophers do - I shall say to you that these qualities themselves seem to me to need explanation. | |
From: René Descartes (The World [1631], 9:25-6), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 1.3 | |
A reaction: Nice. I take pushing the boundaries of explanation back (or down) to be the basic driving force of all human thought, in metaphysics as well as in physics. |
20964 | Descartes said there was conservation of 'quantity of motion' [Descartes, by Papineau] |
Full Idea: Descartes incorporated the conservation of what he called 'quantity of motion', by which he meant mass times speed. | |
From: report of René Descartes (The World [1631]) by David Papineau - Thinking about Consciousness App 2 | |
A reaction: Mass times velocity is now called 'momentum'. Is this the first ever conservation law? There are now lots of them. |