| 16717 | Which of the contrary features of a body are basic to it? [Aristotle] |
| Full Idea: What sorts of contrarities, and how many of them, are to be accounted 'originative sources' of body? | |
| From: Aristotle (Coming-to-be and Passing-away (Gen/Corr) [c.335 BCE], 329b04) | |
| A reaction: Pasnau says these pages of Aristotle are the source of the doctrine of primary and secondary qualities. Essentially, hot, cold, wet and dry are his four primary qualities. |
| 16726 | Why can't we deduce secondary qualities from primary ones, if they cause them? [Buridan] |
| Full Idea: The entire difficulty in this question is why through a knowledge of the primary tangible qualities we cannot come to a knowledge of flavors or odors, since these are their causes, since we often go from knowledge of causes to knowing their effects. | |
| From: Jean Buridan (Questions on Aristotle's Posterior Analytics [1344], I.28c), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 22.2 | |
| A reaction: He is commenting on Idea 16725. Still a nice puzzle in the philosophy of mind. Will neuroscientists ever be able to infer to actual character of some quale, just from the structures of the neurons? |
| 16720 | Secondary qualities come from temperaments and proportions of primary qualities [Conimbricense] |
| Full Idea: Colors, flavours, smells, and other secondary qualities arise from the various temperaments and proportions of the primary qualities. | |
| From: Collegium Conimbricense (Aristotelian commentaries [1595], I.10.4 Gen&C), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 21.2 | |
| A reaction: This is a bit more subtle than merely mixing the primary qualities. What about the powers of the primary qualities? Presumably that is the 'temperaments'? |
| 15989 | Colours, smells and tastes are ideas; the secondary qualities have no colour, smell or taste [Locke, by Alexander,P] |
| Full Idea: If I am right, colours, tastes, odours and sounds are not, for Locke secondary qualities but ideas; secondary qualities are colourless, tasteless, odourless and soundless textures of bodies. | |
| From: report of John Locke (Essay Conc Human Understanding (2nd Ed) [1694]) by Peter Alexander - Ideas, Qualities and Corpuscles 8 | |
| A reaction: This the concise summary of Alexander's reading of Locke, and I find him wholly convincing. |
| 15971 | Secondary qualities are powers of complex primary qualities to produce sensations in us [Locke] |
| Full Idea: Such qualities, which are nothing in objects but powers to produce various sensations in us by their primary qualities i.e. by the bulk, figure, texture, and motion of their sensible parts, as colours, sounds, tastes etc. These I call secondary qualities. | |
| From: John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 2.08.10) | |
| A reaction: Alexander emphasises that secondary qualities are in objects. It is the ideas (here 'sensations') which are in us. This quotation shows that secondary qualities are not identical with 'textures' (which are complex primary qualities), but are 'powers'. |
| 12481 | Hands can report conflicting temperatures, but not conflicting shapes [Locke] |
| Full Idea: The same water may produce the idea of cold by one hand and of heat by the other; ...but figure never produces the idea of a square by one hand which has produced the idea of a globe by the other. | |
| From: John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 2.08.21) | |
| A reaction: I find this to be a thoroughly convincing argument in favour of the primary/secondary distinction, despite the later objects of Berkeley, Hume and Kant. One might add colour blind people reporting differently from the rest of us. |
| 12546 | We can't know how primary and secondary qualities connect together [Locke] |
| Full Idea: There is no discoverable connection between any secondary quality, and those primary qualities that it depends on. | |
| From: John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 4.03.12) | |
| A reaction: I take this to be an accurate account of the problem, and it pinpoints what may be the single most recalcitrant mystery facing human understanding - why do red things look RED? |
| 18264 | We know the shape of a cone from its concept, but we don't know its colour [Kant] |
| Full Idea: The shape of a cone we can form for ourselves in intuition, unassisted by any experience, according to its concept alone, but the colour of this cone must be previously given in some experience or other. | |
| From: Immanuel Kant (Critique of Pure Reason [1781], B743/A715) | |
| A reaction: Coffa says this gives a 'transcendental twist' to the primary/secondary distinction. The distinction doesn't seem to help much, since you clearly don't know the shape of a pebble from its concept. Is the angle of the cone part of its concept? |
| 5453 | Essentialists mostly accept the primary/secondary qualities distinction [Ellis] |
| Full Idea: Essentialists mostly accept the distinction between primary and secondary qualities, ..where the primary qualities of things are those that are intrinsic to the objects that have them. | |
| From: Brian Ellis (The Philosophy of Nature: new essentialism [2002], Ch.3) | |
| A reaction: One reason I favour essentialism is because I have always thought that the primary/secondary distinction was a key to understanding the world. 'Primary' gets at the ontology, 'secondary' shows us the epistemology. |
| 22429 | We achieve objectivity by dropping secondary qualities, to focus on structural primary qualities [Nagel] |
| Full Idea: At the end [of the three stages of objectivity] the secondary qualities drop out of our picture of the external world, and the underlyiing primary qualities such as shape, size, weight, and motion are thought of structurally. | |
| From: Thomas Nagel (The View from Nowhere [1986], II) | |
| A reaction: This is the orthodox view for realists about the external world, and I largely agree. The only problem I see is that secondary qualities contain information, such as the colour of rotting fruit - but then colour is not an essential feature of rot. |
| 3249 | Modern science depends on the distinction between primary and secondary qualities [Nagel] |
| Full Idea: The distinction between primary and secondary qualities is the precondition for the development of modern physics and chemistry. | |
| From: Thomas Nagel (The View from Nowhere [1986], V.3) |
| 7374 | Light wavelengths entering the eye are only indirectly related to object colours [Dennett] |
| Full Idea: The wavelengths of the light entering the eye are only indirectly related to the colours we see objects to be. | |
| From: Daniel C. Dennett (Consciousness Explained [1991], 12.2) | |
| A reaction: This is obviously bad news for naïve realism, but I also take it as good support for the primary/secondary distinction. I just can't make sense of anyone claiming that colour exists anywhere else except in the brain. |
| 22415 | Relativity means differing secondary perceptions are not real disagreements [McGinn] |
| Full Idea: Relativity permits differences in the perceived secondary qualities not to imply genuine disagreement, whereas perceived differences of primary qualities imply that at least one perceiver is in error. | |
| From: Colin McGinn (Subjective View: sec qualities and indexicals [1983], 2) | |
| A reaction: An example of 'relativity' is colour blindness. Sounds good, but what of one perceiver seeing a square as square, and another seeing it obliquely as a parallelogram? The squareness then seems more like a theory than a perception. |
| 22416 | Phenomenalism is correct for secondary qualities, so scepticism is there impossible [McGinn] |
| Full Idea: We might say that scepticism is ruled out for secondary qualities because (roughly) phenomenalism is correct for them; but phenomenalism is not similarly correct for primary qualities, and scepticism cannot get a foothold. | |
| From: Colin McGinn (Subjective View: sec qualities and indexicals [1983], 2) | |
| A reaction: An odd idea, if phenomenalism says that reality consists entirely of phenomena. I should think phenomenalism is a commitment to the absence of primary qualities. |
| 22413 | Being red simply consists in looking red [McGinn] |
| Full Idea: What we should claim is that being red consists in looking red. | |
| From: Colin McGinn (Subjective View: sec qualities and indexicals [1983], 2) | |
| A reaction: A very nice simple account. There is more to being square than looking square (which may not even guarantee that it is square). That's the primary/secondary distinction in a nut shell. But red things don't look red in the dark. Sufficient, not necessary. |
| 22422 | Maybe all possible sense experience must involve both secondary and primary qualities [McGinn] |
| Full Idea: The inseparability thesis about perception says that for any actual and possible sense the content of experiences delivered by that sense must be both of secondary qualities and of primary qualities. | |
| From: Colin McGinn (Subjective View: sec qualities and indexicals [1983], 6) | |
| A reaction: That would mean that all possible experience must have a mode of presentation, and also must be 'of' something independent of experience. So a yellow after-image would not count as an 'experience'? |
| 22428 | You understood being red if you know the experience involved; not so with thngs being square [McGinn] |
| Full Idea: To grasp what it is to be red is to know the kind of sensory experience red things produce; ...but it is not true that to grasp what it is to be square one needs to know what kinds of sensory experience square things produce. | |
| From: Colin McGinn (Subjective View: sec qualities and indexicals [1983], 8) | |
| A reaction: Are any experiences involved in the understanding of squareness? We don't know squareness by a priori intuition (do we?). To grasp squareness if may be necessary to have a variety of experiences of it. Or to grasp that it is primary. |
| 6512 | Secondary qualities have one sensory mode, but primary qualities can have more [Robinson,H] |
| Full Idea: Primary qualities and secondary qualities are often distinguished on the grounds that secondaries are restricted to one sensory modality, but primaries can appear in more. | |
| From: Howard Robinson (Perception [1994], VIII.7) | |
| A reaction: This distinction seems to me to be accurate and important. It is not just that the two types are phenomenally different - it is that the best explanation is that the secondaries depend on their one sense, but the primaries are independent. |
| 7051 | Objects only have secondary qualities because they have primary qualities [Heil] |
| Full Idea: Secondary qualities are not distinct from primary qualities: an object's possession of a given secondary quality is a matter of its possession of certain complex primary qualities. | |
| From: John Heil (From an Ontological Point of View [2003], 17.3) | |
| A reaction: The bottom line here is that, if essentialism is right, colours are not properties at all (see Idea 5456). Heil wants to subsume secondary properties within primary properties. I think we should sharply distinguish them. |