Perhaps, physical and phenomenological are different visual-appearance types {modes of presentation} {presentation modes}, with different principles and properties. However, how can people know that both vision modes are about same feature or object or how modes relate.
Perhaps, motor behavior determines visual perception {motor theory of perception}. However, eye movements do not affect simple visual sense qualities.
Perhaps, visual phenomena require concepts {phenomenal concept}. Phenomenal concepts are sensation types, property types, quality relations, memory indexes, or recognition principles. Phenomenal concepts refer to objects, directly or indirectly, by triggering thought or memory. However, if physical concepts are independent of phenomenal concepts, physical knowledge cannot lead to phenomenal concepts.
Perhaps, in response to stimuli, people have non-physical inner images {sense-datum, image}. Physical objects cause sense data. Sense data are representations. Mind introspects sense data to perceive colors, shapes, and spatial relations. For example, perceived colors are relations between perceivers and sense data and so are mental objects. However, sense data are mental objects, but brain, objects, and neural events are physical, and non-physical inner images cannot reduce to physical events.
Perhaps, coordination among sense and motor systems builds visual information structures {sensorimotor theory of vision}. Sense input and motor output have relations {sensorimotor contingency laws}. Body, head, and eye movements position sensors to gather visual information and remember semantic scene descriptions. Objects have no internal representations, only structural descriptions. Vision is activity, and visual perception depends on coordination between behavior and sensation {enactive perception, Noë} [Noë, 2002] [Noë, 2004] [O'Regan, 1992] [O'Regan and Noë, 2001]. However, perception does not require motor behavior.
Perhaps, different species classify colors differently, because they inhabit different niches {adaptivism}. Perhaps, perceived colors are adaptive relations between objects and color experiences, rather than just categories about physical surfaces. However, experiences are mostly about physical quantities.
Perhaps, perceived color states are relations between perceivers and physical objects {adverbialist theories} {adverbialism} and are neural states, not non-physical mental states. However, experiences do not seem to be relations.
Perhaps, colors are dispositions of physical-object properties to produce visual color states {dispositionalism}. Physical properties dispose perceiver to discriminate and generalize among colors. Colors have no mental qualities. Alternatively, physical-object properties dispose perceivers to experience what it is like to experience color physical properties. Mental qualities allow knowing qualitative similarities among colors. However, experienced colors do not look like dispositions.
Perhaps, perceived colors are representations {intentionalist theories} {intentionalism and vision}, with no qualitative properties. However, afterimages have colors but do not represent physical objects.
Perhaps, colors have mental qualitative properties {mental color}. Mental colors are what it is like for perceivers to have color consciousness. However, mental colors can have no outside physical basis, whereas experienced colors correlate with physical quantities.
Perhaps, colors are objective non-relational physical-object properties and are describable in physical terms {physicalism, color}. For example, physical colors are surface-reflectance ratios. Object surface color remains almost constant during brightness and spectrum changes, because surface reflectances stay constant. Because objects with different surface reflectances can cause same color, physical colors are disjunctions of surface reflectances. However, experience does not provide information about surface reflectances or other physical properties.
Perhaps, perceived colors are physical-object properties or brain states experienced in space {projectivist theories} {projectivism, vision}. However, mental locations are not physical locations. Mental properties cannot be physical properties, because mental states differ from objects.
Perhaps, vision can compare blue, red, and green surface-reflectance ratios between image segments to determine color {retinex theory}. Background brightness is ratio average. Surface neutral colors depend on blue, red, and green reflectance ratios [Land, 1977]. However, vision does not use local or global brightness or reflectance averages.
Three coordinates can define all colors that humans can perceive {trichromacy} {trichromatic vision} {trichromatic theory of color vision} {Young-Helmholtz theory}. Humans have three photopigments in three different cone cells that provide the three coordinates. Trichromatic vision is only in Old World monkeys, apes, and humans.
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Date Modified: 2022.0225