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12. Knowledge Sources / B. Perception / 1. Perception

[process from raw experience to awareness of reality]

34 ideas
Parmenides treats perception and intellectual activity as the same [Theophrastus on Parmenides]
     Full Idea: Parmenides treats perception and intellectual activity as the same.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A46) by Theophrastus - On the Senses 3.1
     A reaction: cf Theaetetus pt 1
Snow is not white, and doesn't even appear white, because it is made of black water [Anaxagoras, by Cicero]
     Full Idea: Anaxagoras not only denied that snow was white, but because he knew that the water from which it was composed was black, even denied that it appeared white to himself.
     From: report of Anaxagoras (fragments/reports [c.460 BCE]) by M. Tullius Cicero - Academica II.100
     A reaction: Not ridiculous. Can you deny that red and yellow balls look orange from a distance? A failure of discrimination on your part. It sounds okay to say 'what I am really perceiving is red and yellow'. [see 'Anaxagoras' poem by D.H.Lawrence!]
Perception is infallible, suggesting that it is knowledge [Plato]
     Full Idea: Perception is always of something that is, and it is infallible, which suggests that it is knowledge.
     From: Plato (Theaetetus [c.368 BCE], 152c)
Our senses could have been separate, but they converge on one mind [Plato]
     Full Idea: It would be peculiar if each of us were like a Trojan horse, with a whole bunch of senses sitting inside us, rather than that all these perceptions converge onto a single identity (mind, or whatever one ought to call it).
     From: Plato (Theaetetus [c.368 BCE], 184d)
Our minds take on the form of what is being perceived [Aristotle, by Mares]
     Full Idea: Aristotle famously holds that in perception our minds take on the form of what is being perceived.
     From: report of Aristotle (De Anima [c.329 BCE]) by Edwin D. Mares - A Priori 08.2
     A reaction: [References in Aristotle needed here...]
Perception necessitates pleasure and pain, which necessitates appetite [Aristotle]
     Full Idea: Where there is perception there is also pleasure and pain, and where there are these, of necessity also appetite.
     From: Aristotle (De Anima [c.329 BCE], 413b23)
Why can't we sense the senses? And why do senses need stimuli? [Aristotle]
     Full Idea: Why is there not also a sense of the senses themselves? And why don't the senses produce sensation without external bodies, since they contain elements?
     From: Aristotle (De Anima [c.329 BCE], 417a03)
Why do we have many senses, and not just one? [Aristotle]
     Full Idea: A possible line of inquiry would be into the question for what purpose we have many senses and not just one.
     From: Aristotle (De Anima [c.329 BCE], 425b04)
Sense organs aren't the end of sensation, or they would know what does the sensing [Aristotle]
     Full Idea: Flesh is not the ultimate sense-organ. To suppose that it is requires the supposition that on contact with the object the sense-organ itself discerns what is doing the discerning.
     From: Aristotle (De Anima [c.329 BCE], 426b16)
Perception of sensible objects is virtually never wrong [Aristotle]
     Full Idea: Perception of the special objects of sense is never in error or admits the least possible amount of falsehood.
     From: Aristotle (De Anima [c.329 BCE], 428b19)
     A reaction: This is, surprisingly, the view which was raised and largely rejected in 'Theaetetus'. It became a doctrine of Epicureanism, and seems to make Aristotle a thoroughgoing empiricist, though that is not so clear elsewhere. I think Aristotle is right.
You cannot understand anything through perception [Aristotle]
     Full Idea: You cannot understand anything through perception. Demonstrations are universal, and universals cannot be perceived.
     From: Aristotle (Posterior Analytics [c.327 BCE], 87b28)
If we have complete healthy senses, what more could the gods give us? [Cicero]
     Full Idea: If human nature were interrogated by some god as to whether it was content with its own senses in a sound and undamaged state or demanded something better, I cannot see what more it could ask for.
     From: M. Tullius Cicero (Academica [c.45 BCE], II.vii.19)
Our images of bodies are not produced by the bodies, but by our own minds [Augustine, by Aquinas]
     Full Idea: Augustine says bodies don't form images in our spirit; our spirit does that itself with amazing quickness. ...So the appearances under which mind knows things aren't drawn from the things themselves.
     From: report of Augustine (works [c.415]) by Thomas Aquinas - Quodlibeta 8.2.1
     A reaction: This is Augustine's theory of 'illumination' - that God creates experience within us. His theory was soon discarded by the early scholastics.
The senses deceive, but also show their own errors [Bacon]
     Full Idea: It is certain that the senses deceive, but they also testify to their own errors.
     From: Francis Bacon (Preface to Great Instauration (Renewal) [1620], p.32), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 22.1
     A reaction: Nice. This is the empiricist view, rather than the rationalist line that reason sorts out the mess created by the senses. Most people know things if you just show them.
'Perception' is basic internal representation, and 'apperception' is reflective knowledge of perception [Leibniz]
     Full Idea: We distinguish between 'perception', the internal state of the monad representing external things, and 'apperception', which is consciousness, or the reflective knowledge of this internal state, not given to all souls, nor at all times to a given soul.
     From: Gottfried Leibniz (Principles of Nature and Grace based on Reason [1714], §4)
     A reaction: The word 'apperception' is standard in Kant. I find it surprising that modern analytic philosophers don't seem to use it when they write about perception. It strikes me as useful, but maybe specialists have a reason for avoiding it.
Not all of perception is accompanied by consciousness [Leibniz]
     Full Idea: I do not think that the Cartesians have ever proved or can prove that every perception is accompanied by consciousness.
     From: Gottfried Leibniz (Principle of Life and Plastic Natures [1705], p.195)
     A reaction: This idea is very important in Leibniz, because non-conscious or barely conscious thoughts and perceptions explain a huge amount about behaviour, reality and morality.
Sensation is not committed to any external object, but perception is [Reid]
     Full Idea: Sensation, by itself, implies neither the conception nor belief of any external object. ...Perception implies a conviction and belief of something external. ...Things so different in their nature ought to be distinguished.
     From: Thomas Reid (Essays on Intellectual Powers 2: Senses [1785], II.16), quoted by Barry Maund - Perception
     A reaction: Maund sees this as the origin of the two-stage view of perception, followed by Chisholm, Evans, Dretske and Lowe. It implies that 'looks', 'tastes', 'sounds' etc. are ambiguous words, having either phenomenal or realist meanings. I like it.
The sensible is distinguished from thought by being about singular things [Hegel]
     Full Idea: The distinction of the sensible from thought is to be located in that fact that the determination of the sensible is singularity.
     From: Georg W.F.Hegel (Logic (Encyclopedia I) [1817], §20 Rem)
     A reaction: Compare Idea 15608, where we find that thought concerns universals. What a very clear thinker Hegel was!
Experience is immediacy, unity, forces, self-awareness, reason, culture, absolute being [Hegel, by Houlgate]
     Full Idea: Experience moves from 1) immediacy, to 2) united objects with properties, 3) its forces and laws, 4) self-consciousness in the process, 5) seeing a rational realm, 6) seeing a cultural realm, 7) seeing the absolute being of consciousness.
     From: report of Georg W.F.Hegel (Phenomenology of Spirit [1807]) by Stephen Houlgate - An Introduction to Hegel 03 'From certainty'
     A reaction: [My summary of Houlgate's summary of the key sequence of ideas in The Phenomenology of Spirit]. I stare at it with bewilderment, but cannot decide whether or not Hegel is pursuing a worthwhile project. [also Houlgate p.77 and 102]
We became increasingly conscious of our sense impressions in order to communicate them [Nietzsche]
     Full Idea: The emergence of our sense impressions into our consciousness, the ability to fix them and, as it were, exhibit them externally, increased proportionally with the need to communicate them to others by means of signs.
     From: Friedrich Nietzsche (The Gay (Joyful) Science [1882], §354)
     A reaction: He says in the same section that such ideas (plus his thoughts on consciousness) are the essence of his 'Perspectivism'. In effect, knowledge is not an individual activity, but a team game
All sense perceptions are permeated with value judgements (useful or harmful) [Nietzsche]
     Full Idea: It cannot be doubted that all sense perceptions are permeated with value judgements (useful and harmful - consequently, pleasant and unpleasant).
     From: Friedrich Nietzsche (The Will to Power (notebooks) [1888], §505)
     A reaction: A thesis expanded by Charles Taylor ('Sources of the Self'). This is a very modern view, but also a very Greek view, which slices through the is/ought distinction.
Perception is either direct realism, indirect realism, or phenomenalism [Dancy,J]
     Full Idea: There are three main families of theories of perception: direct realism, indirect realism, and phenomenalism.
     From: Jonathan Dancy (Intro to Contemporary Epistemology [1985], 10.2)
Perceptual concepts causally influence the content of our experiences [Peacocke]
     Full Idea: Once a thinker has acquired a perceptually individuated concept, his possession of that concept can causally influence what contents his experiences possess.
     From: Christopher Peacocke (A Study of Concepts [1992], 3.3)
     A reaction: Like having 35 different words for 'snow', I suppose. I'm never convinced by such claims. Having the concepts may well influence what you look at or listen to, but I don't see the deliverances of the senses being changed by the concepts.
Perception (which involves an assessment) is a higher state than sensation [Scruton]
     Full Idea: Perception is a higher state than sensation: it involves not just a response to the outer world, but also an assessment of it.
     From: Roger Scruton (Animal Rights and Wrongs [1996], p.14)
     A reaction: This seems to me a simple but really important distinction, even though it wickedly uses the word 'higher', which Greeks like but post-Humeans struggle with. But we all know it is higher, don't we?
Can we reduce perception to acquisition of information, which is reduced to causation or disposition? [Robinson,H]
     Full Idea: Many modern physicalists first analyse perception as no more than the acquisition of beliefs or information through the senses, and then analyse belief and the possession of information in causal or dispositional terms.
     From: Howard Robinson (Perception [1994], V.1)
     A reaction: (He mentions Armstrong, Dretske and Pitcher). A reduction to dispositions implies behaviourism. This all sounds more like an eliminativist strategy than a reductive one. I would start by saying that perception is only information after interpretation.
Would someone who recovered their sight recognise felt shapes just by looking? [Robinson,H]
     Full Idea: Molyneux's Problem is whether someone who was born blind and acquired sight would be able to recognise, on sight, which shapes were which; that is, would they see which shape was the one that felt so-and-so?
     From: Howard Robinson (Perception [1994], VIII.7)
     A reaction: (Molyneux wrote a letter to John Locke about this). It is a good question, and much discussed in modern times. My estimation is that the person would recognise the shapes. We are partly synaesthetic, and see sharpness as well as feeling it.
'Perception' means either an action or a mental state [Chalmers]
     Full Idea: 'Perception' can be used to refer either to the act of perceiving, or the internal state that arises as a result.
     From: David J.Chalmers (The Conscious Mind [1996], 1.2.2)
Perception causes beliefs in us, without inference or justification [Pollock/Cruz]
     Full Idea: Perception is a causal process that inputs beliefs into our doxastic system without their being inferred from or justified on the basis of other beliefs we already have.
     From: J Pollock / J Cruz (Contemporary theories of Knowledge (2nd) [1999], §3.2.3)
     A reaction: This topic is much discussed (e.g. by MacDowell). I don't see how something is going to qualify as a 'belief' if it doesn't involve concepts and propositions. The point that we are caused to have many of our beliefs (rather than judging) seems right.
How can one discriminate yellow from red, but not the colours in between? [Williamson]
     Full Idea: If one takes a spectrum of colours from yellow to red, it might be that given a series of colour samples along that spectrum, each sample is indiscriminable by the naked eye from the next one, though samples at either end are blatantly different.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.151)
     A reaction: This seems like a nice variant of the Sorites paradox (Idea 6008). One could demonstrate it with just three samples, where A and C seemed different from each other, but other comparisons didn't.
An error theory of perception says our experience is not as it seems to be [Martin,M]
     Full Idea: You can end up with an error theory of perception, which says our experience is not as it seems to be, as bizarre as that might be.
     From: Michael Martin (Interview with Baggini and Stangroom [2001], p.140)
     A reaction: This is because of the clash between subjective and objective aspects of perception. It is an enticing proposal, just the sort of thing I pay philosophers to come up with. Given oddities like blindsight, I think it should be taken seriously.
Perception is sensation-then-concept, or direct-concepts, or sensation-saturated-in-concepts [Maund]
     Full Idea: Three forms of (cognitive) direct realism are: two stages - non-conceptual sensory experience, then a non-sensory conceptual state; directly acquiring non-sensuous conceptual states; and sensuous states saturated with concepts.
     From: Barry Maund (Perception [2003], Ch. 3)
     A reaction: [First: Reid, Dretske, Evans, Sellars. Second: Armstrong, Heil, Pitcher, Clark. Third: Kant, McDowell, Strawson, McGinn, Searle]. I find the first one plausible, because of the ambiguity in language, and because unusual experiences separate them.
We have more than five senses; balance and proprioception, for example [Mumford/Anjum]
     Full Idea: The myth of the fivefold division of the sense needs to be overturned. In the experience of causation the senses of balance and proprioception are more important.
     From: S.Mumford/R.Lill Anjum (Getting Causes from Powers [2011], 9.1)
     A reaction: Thinking is a sensual experience too, especially in its emotional dimension. David Hume always based his empiricism on 'experience', not on the mere five external senses.
In phenomenology, all perception is 'seeing as' [Zimmermann,J]
     Full Idea: That human perception is always a 'seeing as' was the cardinal insight of what Husserl called 'phenomenology'.
     From: Jens Zimmermann (Hermeneutics: a very short introduction [2015], 2 'Husserl's')
     A reaction: I presume that 'cardinal insight' means there is no possibility of Husserl being wrong about this. What's happening before you figure out what it is you are looking at?
"My dog's got synaesthesia." How does he smell? ..... [Sommers,W]
     Full Idea: "My dog's got synaesthesia." How does he smell? "Purple."
     From: Will Sommers (talk [2019])