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12. Knowledge Sources / B. Perception / 6. Inference in Perception

[inference is an essential part of perception]

21 ideas
Perception must be an internal matter, because we can fail to perceive when we are preoccupied [Diogenes of Apollonia, by Theophrastus]
     Full Idea: That it is the inner air that perceives, as being a fragment of the god, is shown by the fact that often when our minds are preoccupied with other matters we fail to see or hear.
     From: report of Diogenes (Apoll) (fragments/reports [c.440 BCE], A19) by Theophrastus - On the Senses 42
Particular facts (such as 'is it cooked?') are matters of sense-perception, not deliberation [Aristotle]
     Full Idea: Deliberation is not concerned with particular facts, such as 'is it a loaf?' or 'is it properly cooked?'; these are matters of sense-perception.
     From: Aristotle (Nicomachean Ethics [c.334 BCE], 1112b33)
     A reaction: This seems to be Aristotle's commitment to direct cognition through perception, though if pressed he might concede that concepts (such as 'cooked') are involved in perception.
Molyneux's Question: could a blind man distinguish cube from sphere, if he regained his sight? [Locke]
     Full Idea: Mr Molyneux's Question: a blind man, taught by touch to distinguish between a cube and a sphere of the same metal and same bigness. Suppose the cube and sphere placed on a table, and the man made to see - could he distinguish them?
     From: John Locke (Essay Conc Human Understanding (2nd Ed) [1694], 2.09.08)
     A reaction: Both Molyneux and Locke agree that the answer is 'no', because he won't yet have learned to associate the new experiences with the old shapes. [Gareth Evans wrote on this question]
Truth arises among sensations from grounding reasons and from regularities [Leibniz]
     Full Idea: The truth of sensible things is established by the links amongst them; these depend upon intellectual truths, grounded in reason, and upon observations of regularities among sensible things themselves, even when the reasons are not apparent.
     From: Gottfried Leibniz (New Essays on Human Understanding [1704], 4.11)
     A reaction: It's not clear why regularities would establish truths, given that most hallucinations have regularities in them. I'm thinking that Leibniz is not sufficiently rationalist here, and that it is the rational coherence of experience which validates it.
Appearances have a 'form', which indicates a relational order [Kant]
     Full Idea: That which allows the manifold of appearance to be intuited as ordered in certain relations I call the 'form' of appearance.
     From: Immanuel Kant (Critique of Pure Reason [1781], B034/A20)
     A reaction: An important idea, which figures prominently in Wittgenstein's Tractatus. Presumably the noumenon is responsible for generating the form in the appearances, and we infer the order of the world thereby (though we can't prove it).
I immediately know myself, and anything beyond that is an inference [Fichte]
     Full Idea: Immediately I know only of myself. What I am able to know beyond that I am only able to know through inference.
     From: Johann Fichte (The Vocation of Man [1800], 1)
     A reaction: A direct descendant of the Cartesian Cogito, I assume. Personally, if I bang my head on a beam I take the beam to be a full paid-up member of reality. Is it not possible that he also knows himself through inference? Do animals infer reality?
In man the lowest senses of smell and taste elevate themselves to intellectual acts [Feuerbach]
     Full Idea: Even the lowest senses, smell and taste, elevate themselves in man to intellectual and scientific acts.
     From: Ludwig Feuerbach (Principles of Philosophy of the Future [1843], §53)
     A reaction: Since Darwin we have, I am glad to say, lost this need to distinguish what is 'low' or 'high', and to try to show that even our 'lowest' functions are on the 'high' side. Personally, though, I still need the low/high distinction in moral thinking.
Most perception is one-tenth observation and nine-tenths inference [Mill]
     Full Idea: In almost every act of our perceiving faculties, observation and inference are intimately blended. What we are said to observe is usually a compound result, of which one-tenth may be observation, and the remaining nine-tenths inference.
     From: John Stuart Mill (System of Logic [1843], 4.1.2), quoted by Peter Lipton - Inference to the Best Explanation (2nd) 11 'The scientific'
     A reaction: We seem to think that his kind of observation is a great realisation of twentieth century thought, but thoughtful empiricists spotted it much earlier.
An affirmative belief is present in every basic sense impression [Nietzsche]
     Full Idea: Belief is already present in every sense impression going back to the very moment it begins: and kind of Yes-saying first intellectual activity!
     From: Friedrich Nietzsche (Unpublished Notebooks 1884-85 [1884], 25[168])
     A reaction: He seems right that there is an intrinsic commitment to believing sense impressions, even in animals. Presumably more of a default setting than an intellectual choice.
The evidence of the senses is falsified by reason [Nietzsche]
     Full Idea: 'Reason' is the cause of our falsification of the evidence of the senses.
     From: Friedrich Nietzsche (Twilight of the Idols [1889], 2.1)
     A reaction: One for McDowell.
Broad rejects the inferential component of the representative theory [Broad, by Maund]
     Full Idea: Broad, one of the most important modern defenders of the representative theory of perception, explicitly rejects the inferential component of the theory.
     From: report of C.D. Broad (Mind and Its Place in Nature [1925]) by Barry Maund - Perception Ch.1
     A reaction: Since the supposed inferences happen much too quickly to be conscious, it is hard to see how we could distinguish an inference from an interpretation mechanism. Personally I interpret things long before the question of truth arises.
Inference in perception is unconvincingly defended as non-conscious and almost instantaneous [Harré/Madden]
     Full Idea: To the objection that one is never aware of inferences in sensation, the unconvincing reply comes that such inferences are automatic, telescoped, non-discursive and unconscious.
     From: Harré,R./Madden,E.H. (Causal Powers [1975], 3.II)
     A reaction: I think the 'unconvincing' reply is a bit more convincing in the light of modern research on the brain, which presents everything it does in a far less conscious light than the traditional view. Even reason seems barely conscious.
Experiences have no conceptual content [Evans, by Greco]
     Full Idea: In Evans's work experiences are conceived of as not having a conceptual content at all.
     From: report of Gareth Evans (The Varieties of Reference [1980]) by John Greco - Justification is not Internal
     A reaction: I presume it is this view which provoked McDowell's contrary view in 'Mind and World'. I say this is a job for neuroscience, and I struggle to see what philosophical questions hang on the outcome. I think I side with Evans.
We have far fewer colour concepts than we have discriminations of colour [Evans]
     Full Idea: Do we really understand the proposal that we have as many colour concepts as there are shades colour that we can sensibly discriminate?
     From: Gareth Evans (The Varieties of Reference [1980], 7.5)
     A reaction: This is the argument (rejected by McDowell) that experience cannot be conceptual because experience is too rich. We should not confuse lack of concepts with lack of words. I may have a concept of a colour between two shades, but no word for it.
Maybe explaining the mechanics of perception will explain the concepts involved [Fodor]
     Full Idea: Why mightn't fleshing out the standard psychological account of perception itself count as learning what perceptual justification amounts to?
     From: Jerry A. Fodor (In a Critical Condition [2000], Ch. 1)
Perception has proto-propositions, between immediate experience and concepts [Peacocke]
     Full Idea: Perceptual experience has a second layer of nonconceptual representational content, distinct from immediate 'scenarios' and from conceptual contents. These additional contents I call 'protopropositions', containing an individual and a property/relation.
     From: Christopher Peacocke (A Study of Concepts [1992], 3.3)
     A reaction: When philosophers start writing this sort of thing, I want to turn to neuroscience and psychology. I suppose the philosopher's justification for this sort of speculation is epistemological, but I see no good coming of it.
If perception is much richer than our powers of description, this suggests that it is non-conceptual [Crane]
     Full Idea: The richness in information of perceptual experience outruns our modes of description of it, which has led some philosophers to claim that the content of perceptual experience is non-conceptual.
     From: Tim Crane (Elements of Mind [2001], 5.45)
     A reaction: It certainly implies that it can't be entirely conceptual, but it still may be that in humans concepts are always involved. Not when I'm waking up in the morning, though.
Sense evidence is not beliefs, because they are about objective properties, not about appearances [Pollock/Cruz]
     Full Idea: We think it is a mistake to suppose that the evidence of our senses comes to us in the form of beliefs; in perception, the beliefs we form are almost invariably about the objective properties of physical objects - not about how they appear to us.
     From: J Pollock / J Cruz (Contemporary theories of Knowledge (2nd) [1999], §2.5.5)
     A reaction: The tricky word here is 'evidence'. At what point in the process of perception does something begin to count as evidence? It must at least involve concepts (and maybe even propositions) if it is going to be thought about in that way.
Perception is a mode of belief-acquisition, and does not involve sensation [Lowe]
     Full Idea: According to one school of thought, perception is simply a mode of belief-acquisition,and there is no reason to suppose that any element of sensation is literally involved in perception.
     From: E.J. Lowe (Locke on Human Understanding [1995], Ch.3)
     A reaction: Blindsight would be an obvious supporting case for this view. I think this point is crucial in understanding what is wrong with Jackson's 'knowledge argument' (involving Mary, see Idea 7377). Sensation gives knowledge, so it can't be knowledge.
One thesis says we are not aware of qualia, but only of objects and their qualities [Maund]
     Full Idea: The representationalist/intentionalist thesis about perception is that we are not aware of the intrinsic qualities of experience in normal perception; we are instead aware of those objects and their qualities that are specified in the content.
     From: Barry Maund (Perception [2003], Ch. 9)
     A reaction: If secondary qualities are in the mind, not in objects, how come people always thought they were in objects? Answer: because this thesis is right? The primary mode of the mind is projected outwards, though we can introspect about colours. [Dretske]
The Myth of the Given claims that thought is rationally supported by non-conceptual experiences [Maund]
     Full Idea: The so-called 'myth of the given' is the view that conceptual content can be rationally supported by experiences construed as states with non-conceptual content.
     From: Barry Maund (Perception [2003], Ch.10)
     A reaction: The myth is attacked by Sellars and McDowell, the latter claiming that concepts must be embedded in the experiences. Maybe only realism is required to make the Given work. The experiences are definitely of something, and off we go...