Direct and indirect realism
In the 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;[1][2] 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.
For representationalism in the arts, see Realism (visual arts).
Indirect 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.[3] 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.[4]
Conversely, direct 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.
Aristotle was the first to provide a description of direct realism. In On the Soul he describes how a see-er is informed of the object itself by way of the hylomorphic form carried over the intervening material continuum with which the eye is impressed.[5]
In medieval philosophy, direct realism was defended by Thomas Aquinas.[5]
Indirect realism was popular with several early modern philosophers, including René Descartes,[6] John Locke,[6] G. W. Leibniz,[7] and David Hume.[8]
Locke categorized qualities as follows:[9]
Thomas Reid, a notable member of the Scottish common sense realism was a proponent of direct realism.[10] Direct realist views have been attributed to Baruch Spinoza.[11]
Late modern philosophers, J. G. Fichte and G. W. F. Hegel followed Kant in adopting empirical realism.[12][13] Direct realism was also defended by John Cook Wilson in his Oxford lectures (1889–1915).[14] On the other hand, Gottlob Frege (in his 1892 paper "Über Sinn und Bedeutung") subscribed to indirect realism.[15]
In contemporary philosophy, indirect realism has been defended by Edmund Husserl[16] and Bertrand Russell.[8] Direct realism has been defended by Hilary Putnam,[17] John McDowell,[18][19] Galen Strawson,[20] and John R. Searle.[21]
However, epistemological dualism 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,[22] 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;[23] George Steiner refers to our personal use of language as an "idiolect", one particular to ourselves in its detail.[24] 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.[25]