In philosophy of perception and philosophy of mind, direct (or naïve) realism, as opposed to indirect (or representational) realism, are differing models that describe the nature of conscious experiences.Lehar, Steve. (2000). The Function of Conscious Experience: An Analogical Paradigm of Perception and Behavior , Consciousness and Cognition.Lehar, Steve. (2000). Naïve Realism in Contemporary Philosophy , The Function of Conscious Experience. The debate arises out of the metaphysical question of whether the world we see around us is the real world itself or merely an internal perceptual copy of that world generated by our conscious experience.
Indirect perceptual realism is broadly equivalent to the scientific view of perception that subjects do not experience the external world as it really is, but perceive it through the lens of a conceptual framework.Schacter, Daniel (2011). Psychology. Worth Publishers. ISBN 9781429237192. Furthermore, indirect realism is a core tenet of the cognitivism paradigm in psychology and cognitive science. While there is superficial overlap, the indirect model is unlike the standpoint of idealism, which holds that only ideas are real, but there are no mind-independent objects.
Conversely, direct perceptual realism postulates that conscious subjects view the world directly, treating concepts as a 1:1 correspondence. Furthermore, the framework rejects the premise that knowledge arrives via a representational medium, as well as the notion that concepts are interpretations of sensory input derived from a real external world.
History Aristotle was the first to provide a description of direct realism. In On the Soul he describes how a seer is informed of the object itself by way of the hylomorphic form carried over the intervening material continuum with which the eye is impressed. In medieval philosophy, direct realism was further defended by Thomas Aquinas.
Indirect realism was popular with several early modern philosophers, including René Descartes,John W. Yolton, Realism and Appearances: An Essay in Ontology, Cambridge University Press, 2000, p. 136. John Locke, G. W. Leibniz,A. B. Dickerson, Kant on Representation and Objectivity, Cambridge University Press, 2003, p. 85. and David Hume.The Problem of Perception (Stanford Encyclopedia of Philosophy) : "Paraphrasing David Hume (1739...; see also Locke 1690, Berkeley 1710, Russell 1912): nothing is ever directly present to the mind in perception except perceptual appearances."
Locke categorized qualities as follows:A. D. Smith, "On Primary and Secondary Qualities", Philosophical Review (1990), 221–54. Primary qualities are qualities which are "explanatorily basic" – which is to say, they can be referred to as the explanation for other qualities or phenomena without requiring explanation themselves – and they are distinct in that our sensory experience of them resembles them in reality. (For example, one perceives an object as spherical precisely because of the way the atoms of the sphere are arranged.) Primary qualities cannot be removed by either thought or physical action, and include mass, movement, and, controversially, solidity (although later proponents of the distinction between primary and secondary qualities usually discount solidity). Secondary qualities are qualities that one's experience does not directly resemble; for example, when one sees an object as red, the sensation of seeing redness is not produced by some quality of redness in the object, but by the arrangement of atoms on the surface of the object which reflects and absorbs light in a particular way. Secondary qualities include colour, smell, sound, and taste.
Thomas Reid, a notable member of the Scottish common sense realism was a proponent of direct realism.Patrick Rysiew, New Essays on Thomas Reid, Routledge, 2017, p. 18. Direct realist views have been attributed to Baruch Spinoza.Michael Della Rocca (ed.), The Oxford Handbook of Spinoza, Oxford University Press, 2017, p. 288.
Late modern philosophers, J. G. Fichte and G. W. F. Hegel followed Kant in adopting empirical realism.Daniel Breazeale and Tom Rockmore (eds.), Fichte, German Idealism, and Early Romanticism, Rodopi, 2010, p. 20.Tom Rockmore, Before and After Hegel: A Historical Introduction to Hegel's Thought, Hackett Publishing, 2003, p. xviii: "Hegel follows Kant ... in limiting claims to know to the empirically real. In short, he adopts a view very similar to Kant's empirical realism." Direct realism was also defended by John Cook Wilson in his Oxford lectures (1889–1915).Michael Beaney (ed.), The Oxford Handbook of the History of Analytic Philosophy, Oxford University Press, 2013, p. 40. On the other hand, Gottlob Frege (in his 1892 paper "Über Sinn und Bedeutung") subscribed to indirect realism about propositional content.Samuel Lebens, Bertrand Russell and the Nature of Propositions: A History and Defence of the Multiple Relation Theory of Judgement, Routledge, 2017, p. 34.
In contemporary philosophy, indirect realism has been defended by Edmund HusserlRobin D. Rollinger, Husserl's Position in the School of Brentano, Phaenomenologica 150, Dordrecht: Kluwer, 1999, p. 224 n. 1. and Bertrand Russell. Direct realism has been defended by Hilary Putnam,Putnam, Hilary. Sep. 1994. "The Dewey Lectures 1994: Sense, Nonsense, and the Senses: An Inquiry into the Powers of the Human Mind." The Journal of Philosophy 91(9):445–518. John McDowell,John McDowell, Mind and World. Harvard University Press, 1994, p. 26.Roger F. Gibson, "McDowell's Direct Realism and Platonic Naturalism", Philosophical Issues Vol. 7, Perception (1996), pp. 275–281. Galen Strawson,Galen Strawson, "Real Direct Realism" , a lecture recorded 2014 at Marc Sanders Foundation, Vimeo. and John R. Searle.John R. Searle, Seeing Things as They Are: A Theory of Perception, Oxford University Press, 2015, p. 15.
However, indirect realism has come under sustained attack by other contemporary philosophers, such as Ludwig Wittgenstein (the private language argument) and Wilfrid Sellars in his seminal essay "Empiricism and the Philosophy of Mind". Indirect realism is argued to be problematical because of Ryle's regress and the homunculus argument. Recently, reliance on the private language argument and the "homunculus objection" has itself come under attack. It can be argued that those who argue for "inner presence", to use Antti Revonsuo's term,Revonsuo, Antti (2006) Inner Presence: Consciousness as a Biological Phenomenon, Cambridge MA: MIT Press. are not proposing a private "referent", with the application of language to it being "private" and thus unshareable, but a private use of public language. There is no doubt that each of us has a private understanding of public language, a notion that has been experimentally supported;Rommetveit, Ragnar (1974) On Message Structure: A Framework for the Study of Language and Communication, London: John Wiley & Sons. George Steiner refers to our personal use of language as an "idiolect", one particular to ourselves in its detail.Steiner, George (1998), After Babel: Aspects of Language and Translation, London & New York: Oxford University Press. The question has to be put how a collective use of language can go on when, not only do we have differing understandings of the words we use, but our sensory registrations differ.Hardin, C. L. (1988) Color for Philosophers, Indianapolis IN: Hackett Pub. Co.
Arguments against direct realism
Argument from illusion
This argument was "first offered in a more or less fully explicit form in Berkeley (1713)." It is also referred to as the problem of conflicting appearances (e.g. Myles Burnyeat's article Conflicting Appearances). It has been argued that "informed commonsense" indicates that perceptions often depend on organs of perception.Naïve Realism , University of Reading. For example, humans would receive visual information very differently if they, like flies, had compound eyes, and may not even be able to imagine how things would appear with entirely different sense organs such as infra-red detectors or echo-location devices. Furthermore, perception systems can misrepresent objects even when in full working order, as shown, for example, by optical illusions like the Müller-Lyer illusion. More dramatically, sometimes people perceive things which are not there at all, which can be termed instances of "hallucination" or "perceptual delusion".
The argument from illusion allegedly shows the need to posit sense-data as the immediate objects of perception. In cases of illusion or hallucination, the object has qualities that no public physical object in that situation has and so must be distinct from any such object. Naïve realism may accommodate these facts as they stand by virtue of its very vagueness (or "open-texture"): it is not specific or detailed enough to be refuted by such cases. A more developed direct realist might respond by showing that various cases of misperception, failed perception, and perceptual relativity do not make it necessary to suppose that sense-data exist. When a stick submerged in water looks bent a direct realist is not compelled to say the stick actually is bent but can say that the stick can have more than one appearance: a straight stick can look bent when light reflected from the stick arrives at one's eye in a crooked pattern, but this appearance is not necessarily a sense-datum in the mind. Similar things can be said about the coin which appears circular from one vantage point and oval-shaped from another. Pressing on your eyeball with a finger creates double vision but assuming the existence of two sense-data is unnecessary: the direct realist can say that they have two eyes, each giving them a different view of the world. Usually the eyes are focused in the same direction; but sometimes they are not.
However, this response is presumably based on previously observed data. If one were to be able to observe nothing other than the stick in the water, with no previous information, it would appear that the stick was bent. Visual depth in particular is a set of inferences, not an actual experience of the space between things in a radial direction outward from the observation point.Green, Alex. (2003). The Empirical Description of Conscious Experience , The Science and Philosophy of Consciousness. If all empirical evidence is based upon observation then the entire developed memory and knowledge of every perception and of each sense may be as skewed as the bent stick. Since objects with different qualities are experienced from each of the different perspectives there is no apparent experiential basis for regarding one out of any such set of related perceptual experiences as the one in which the relevant physical object is itself immediately experienced. The most reasonable conclusion is that the experienced object is always distinct from the physical object or at least that there is no way to identify which, if any, of the immediately experienced objects is the physical object itself. Epistemologically it is as though physical objects were never given, whether or not that is in fact the case.