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12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory

[theory that sense-data actually exist]

23 ideas
The qualities of the world are mere appearances; reality is the motions which cause them [Hobbes]
     Full Idea: Whatsoever accidents or qualities our senses make us think there be in the world, they are not there, but are seemings and apparitions only. The things that really are in the world without us are those motions by which these seemings are caused.
     From: Thomas Hobbes (The Elements of Law [1640], I.2.10), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 10.2
     A reaction: This seems to count as a sense-datum theory, rather than a representative theory of perception, since it makes no commitment to the qualities containing any accurate information at all. We just start from the qualities and try to work it out.
Appearance and reality can be separated by mirrors and echoes [Hobbes]
     Full Idea: If colours or sounds were in the bodies or objects that cause them, they could not be severed from them, as by glasses, and in echoes by reflection, we see they are; where we know the thing we see is in one place, the appearance in another.
     From: Thomas Hobbes (Leviathan [1651], 1.01)
Direct feeling of the senses are merely data; perception of the world comes with understanding causes [Schopenhauer]
     Full Idea: What the eye, the ear, or the hand feels, is not perception, it is merely data. Only when the understanding passes from the effect to the cause does the world lie before us as perception extended in space.
     From: Arthur Schopenhauer (The World as Will and Idea [1819], I 004)
     A reaction: These certainly seems to be a sense-data theory. Philosophers are much more ready to separate the data from the understanding than neuroscientists are.
In 1921 Russell abandoned sense-data, and the gap between sensation and object [Russell, by Grayling]
     Full Idea: In 'The Analysis of Mind' Russell gave up talk of 'sense-data', and ceased to distinguish between the act of sensing and what is sensed.
     From: report of Bertrand Russell (The Analysis of Mind [1921]) by A.C. Grayling - Russell Ch.2
     A reaction: This seems to lead towards the modern 'adverbial' account of sensing, where I don't sense 'data', but where qualia (such as redness) are our particular mode of directly perceiving objects, where insects might directly perceive them in a different mode.
Seeing is not in itself knowledge, but is separate from what is seen, such as a patch of colour [Russell]
     Full Idea: Undeniably, knowledge comes through seeing, but it is a mistake to regard the mere seeing itself as knowledge; if we are so to regard it, we must distinguish the seeing from what is seen; a patch of colour is one thing, and our seeing it is another.
     From: Bertrand Russell (The Analysis of Mind [1921], Lec. VIII)
     A reaction: This is Russell's 1921 explanation of why he adopted sense-data (but he rejects them later in this paragraph). This gives a simplistic impression of what he intended, which has three components: the object, the 'sensibile', and the sense-datum.
After 1912, Russell said sense-data are last in analysis, not first in experience [Russell, by Grayling]
     Full Idea: During the decade after 'Problems of Philosophy' Russell points our repeatedly that specifications of sense-data come last in analysis, not first in experience.
     From: report of Bertrand Russell (Problems of Philosophy [1912]) by A.C. Grayling - Russell Ch.2
     A reaction: This was a symptom of Russell losing faith in sense-data, and he eventually abandoned them. There is a possible position where we deny any such item as sense-data in a scientific account, but allow them in our metaphysics.
'Sense-data' are what are immediately known in sensation, such as colours or roughnesses [Russell]
     Full Idea: Let us give the name 'sense-data' to the things that are immediately known in sensation: such things as colours, sounds, smells, hardnesses, roughnesses, and so on.
     From: Bertrand Russell (Problems of Philosophy [1912], Ch. 1)
     A reaction: This idea gradually became notorious, because it seems to create a new ontological category unnecessarily, and it creates problems, such as how the intermediary interacts with us and with things. Are sense-data totally non-conceptual?
We live in sense-data, but talk about physical objects [Wittgenstein]
     Full Idea: The world we live in is the world of sense-data, but the world we talk about is the world of physical objects.
     From: Ludwig Wittgenstein (Lectures 1930-32 (student notes) [1931], p.82), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 13 'Verif'
     A reaction: I really like that one. Even animals, I surmise, think of objects quite differently from the way they immediately experience them.
Positivists prefer sense-data to objects, because the vocabulary covers both illusions and perceptions [Ayer, by Robinson,H]
     Full Idea: Positivists prefer the sense-datum vocabulary because it is more inclusive than physical object vocabulary; it can report after-images, hallucinations, illusions and bodily sensations, as well as veridical perceptions.
     From: report of A.J. Ayer (Language,Truth and Logic [1936]) by Howard Robinson - Perception IX.4
     A reaction: The assumption of this is that illusions and perceptions are frequently indistinguishable, but that is just nonsense. Illusions usually appeal to one sense only, when you are ill, and in an unclear way. Sensible people know objects when they see them.
The concept of sense-data allows us to discuss appearances without worrying about reality [Ayer]
     Full Idea: The introduction of the term 'sense-datum' is a means of referring to appearances without prejudging the question of what it is, if anything, that they are appearances of.
     From: A.J. Ayer (Phenomenalism [1947], §1)
Maybe 'sense-data' just help us to talk about unusual perceptual situations [Lacey]
     Full Idea: One possibility is that talk of sense-data is a mere linguistic convenience, providing a noun for talking about appearances, as when seeing a red object in sodium light (when it looks grey).
     From: A.R. Lacey (A Dictionary of Philosophy [1976], p.196)
     A reaction: The term seems to have been coined to deal with situations where there is a gap between appearance and presumed reality, as in illusions. Maybe illusions prove the existence of sense-data, rather than it being a 'convenient' term.
Sense-data are neutral uninterpreted experiences, separated from objects and judgements [Angeles]
     Full Idea: Sense-data are that which is given to us directly and immediately such as colour, shape, smell, without identification of them as specific material objects; they are usually thought to be devoid of judgment, interpretation, bias, preconception.
     From: Peter A. Angeles (A Dictionary of Philosophy [1981], p.254)
     A reaction: This definition makes them clearly mental (rather than being qualities of objects), and they sound like Hume's 'impressions'. They are not features of the external world, but the first steps we make towards experience.
We can be looking at distant stars which no longer actually exist [Dancy,J]
     Full Idea: An object such as a distant star can have ceased to exist by the moment at which we are directly aware of it.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.2)
Visual sense data are an inner picture show which represents the world [Blackburn]
     Full Idea: In the case of vision, sense data are a kind of inner picture show which itself only indirectly represents aspects of the external world.
     From: Simon Blackburn (Oxford Dictionary of Philosophy [1994], p.347)
     A reaction: I'm unsure whether this is correct. Russell says the 'roughness' of the table is the sense datum. If it is even a possibility that there are unsensed sense-data, then they cannot be an aspect of the mind, as Blackburn is suggesting they are.
Sense data avoid the danger of misrepresenting the world [Williams,M]
     Full Idea: The point of insisting on the absolute immediacy of sense data is that representation always seems to involve the possibility of misrepresentation.
     From: Michael Williams (Problems of Knowledge [2001], Ch. 8)
Sense data imply representative realism, possibly only representing primary qualities [Audi,R]
     Full Idea: A sense-datum theory might be called a representative realism because it conceives perception as a relation in which sense-data represent perceived external (hence real) objects to us. For Locke they were resemblances only of primary qualities.
     From: Robert Audi (Epistemology: contemporary introduction [1998], I p.33)
Sense-data (and the rival 'adverbial' theory) are to explain illusions and hallucinations [Audi,R]
     Full Idea: The sense-datum theory is mainly to explain hallucinations and illusions, though there might be other theories, such as the 'adverbial' theory.
     From: Robert Audi (Epistemology: contemporary introduction [1998], I p.36)
Sense-data leads to either representative realism or phenomenalism or idealism [Robinson,H]
     Full Idea: The sense-datum theorist is either a representative realist or a phenomenalist (with which we can classify idealism for present purposes).
     From: Howard Robinson (Perception [1994], VII.5)
     A reaction: The only alternative to these two positions seems to be some sort of direct realism. I class myself as a representative realist, as this just seems (after a very little thought about colour blindness) to be common sense. I'm open to persuasion.
One can taste that the wine is sour, and one can also taste the sourness of the wine [Crane]
     Full Idea: One can taste that the wine is sour, and one can also taste the sourness of the wine.
     From: Tim Crane (Elements of Mind [2001], 5.42)
     A reaction: …so sense data are optional? We create sense data by objectifying them, but animals just taste the wine, and are direct realists. Tasting the sourness seems to be a case of abstraction.
The traditional supports for the sense datum theory were seeing double and specks before one's eyes [Crane]
     Full Idea: The traditional examples used to support the sense datum theory were seeing double and specks before one's eyes.
     From: Tim Crane (Elements of Mind [2001], 5.43)
     A reaction: Presumably, though, direct realists can move one eye, or having something wrong with a retina.
The structure of the retina has already simplified the colour information which hits it [Chalmers]
     Full Idea: In vision three varieties of cones abstract out information according to the amount of light present in various overlapping wavelength ranges. Immediately, many distinctions present in the original light wave are lost.
     From: David J.Chalmers (The Conscious Mind [1996], 3.8.3)
'Sense-data' arrived in 1910, but it denotes ideas in Locke, Berkeley and Hume [Mautner]
     Full Idea: The term 'sense-data' gained currency around 1910, through writings of Moore and Russell, but it seems to denote at least some of the things referred to as 'ideas of sense' (Locke), or 'ideas' and 'sensible qualities' (Berkeley), or 'impressions' (Hume).
     From: Thomas Mautner (Penguin Dictionary of Philosophy [1996], p.518)
     A reaction: See also Hobbes in Idea 2356 for an even earlier version. It looks as if the concept of sense-data is almost unavoidable for empiricists, and yet most modern empiricists have rejected them. You still have to give an account of perceptual illusions.
Sense-data have an epistemological purpose (foundations) and a metaphysical purpose (explanation) [Maund]
     Full Idea: Sense-data have an epistemological purpose (to serve as foundations on which the edifice of knowledge is to be constructed), and a metaphysical purpose (to provide an accurate account of the phenomenology of perceptual experience).
     From: Barry Maund (Perception [2003], Ch. 6)
     A reaction: This is very important, because there is a real danger (e.g. in Russell) that the epistemological convenience of sense-data for giving reliability in knowledge means that we are too quick in making the assumption that they actually exist.