Hard problem of consciousness

[1][2] It is contrasted with the "easy problems" of explaining why and how physical systems give a (healthy) human being the ability to discriminate, to integrate information, and to perform behavioral functions such as watching, listening, speaking (including generating an utterance that appears to refer to personal behaviour or belief), and so forth.

[1] The easy problems are amenable to functional explanation—that is, explanations that are mechanistic or behavioral—since each physical system can be explained (at least in principle) purely by reference to the "structure and dynamics" that underpin the phenomenon.

[7] In 1996, Chalmers published The Conscious Mind, a book-length treatment of the hard problem, in which he elaborated on his core arguments and responded to counterarguments.

It has been accepted by some philosophers of mind such as Joseph Levine,[10] Colin McGinn,[11] and Ned Block[12] and cognitive neuroscientists such as Francisco Varela,[13] Giulio Tononi,[14][15] and Christof Koch.

[14][15] On the other hand, its existence is denied by other philosophers of mind, such as Daniel Dennett,[16] Massimo Pigliucci,[17] Thomas Metzinger, Patricia Churchland,[18] and Keith Frankish,[19] and by cognitive neuroscientists such as Stanislas Dehaene,[20] Bernard Baars,[21] Anil Seth,[22] and Antonio Damasio.

Ned Block believes that there exists a "Harder Problem of Consciousness", due to the possibility of different physical and functional neurological systems potentially having phenomenal overlap.

For example, the rings of Saturn are a physical thing because they are nothing more than a complex arrangement of a large number of subatomic particles interacting in a certain way.

"[50] Daniel Dennett, a philosopher of mind, criticised the field's use of "the zombie hunch" which he deems an "embarrassment"[51] that ought to "be dropped like a hot potato".

[52] For example, Nagel put forward a "speculative proposal" of devising a language that could "explain to a person blind from birth what it is like to see.

Other researchers accept the problem as real and seek to develop a theory of consciousness' place in the world that can solve it, by either modifying physicalism or abandoning it in favour of an alternative ontology (such as panpsychism or dualism).

[54] The labelling convention of this taxonomy has been incorporated into the technical vocabulary of analytic philosophy, being used by philosophers such as Adrian Boutel,[55] Raamy Majeed,[56] Janet Levin,[57] Pete Mandik & Josh Weisberg,[58] Roberto Pereira,[59] and Helen Yetter-Chappell.

[54] Thinkers who subscribe to type-A materialism include Paul and Patricia Churchland, Daniel Dennett, Keith Frankish, and Thomas Metzinger.

[45] Broadly, strong reductionists accept that conscious experience is real but argue it can be fully understood in functional terms as an emergent property of the material brain.

[70] Eliminative materialism or eliminativism is the view that many or all of the mental states used in folk psychology (i.e., common-sense ways of discussing the mind) do not, upon scientific examination, correspond to real brain mechanisms.

[78] For example, in his book Consciousness and the Social Brain neuroscientist Michael Graziano advocates what he calls attention schema theory, in which our perception of being conscious is merely an error in perception, held by brains which evolved to hold erroneous and incomplete models of their own internal workings, just as they hold erroneous and incomplete models of their own bodies and of the external world.

One highly cited example comes from the philosopher Galen Strawson who wrote an article in the New York Review of Books titled "The Consciousness Deniers".

"[87] Another notable example comes from Christof Koch (a neuroscientist and one of the leading proponents of Integrated Information Theory) in his popular science book The Feeling of Life Itself.

In the early pages of the book, Koch describes eliminativism as the "metaphysical counterpart to Cotard's syndrome, a psychiatric condition in which patients deny being alive.

"[91][92] In relation to Type-B Materialism, those who believe that our intuitions about the hard problem are innate (and therefore common to all humans) subscribe to the "hard-wired view".

This is similar to Type-B Materialism, but it makes the further claim that the psychological facts that cause us to intuit the hard problem are not innate, but culturally conditioned.

[54] This is described by analogy to progression in other areas of science, such as mass-energy equivalence which would have been unfathomable in ancient times,[54] abiogenesis which was once considered paradoxical from an evolutionary framework,[102][101] or a suspected future theory of everything combining relativity and quantum mechanics.

Principally, the basis for the argument arises from the apparently high correlation of consciousness with living brain tissue,[106] thereby rejecting panpsychism[104] without explicitly formulating physical causation.

"[130] New mysterianism, most significantly associated with the philosopher Colin McGinn, proposes that the human mind, in its current form, will not be able to explain consciousness.

[131] His position is that a naturalistic explanation does exist but that the human mind is cognitively closed to it due to its limited range of intellectual abilities.

[45] Steven Pinker has also endorsed this weaker version of the view, summarizing it as follows:[9] And then there is the theory put forward by philosopher Colin McGinn that our vertigo when pondering the Hard Problem is itself a quirk of our brains.

[9][133][better source needed] Since 1990, researchers including the molecular biologist Francis Crick and the neuroscientist Christof Koch have made significant progress toward identifying which neurobiological events occur concurrently to the experience of subjective consciousness.

Integrated information theory (IIT), developed by the neuroscientist and psychiatrist Giulio Tononi in 2004 and more recently also advocated by Koch, is one of the most discussed models of consciousness in neuroscience and elsewhere.

[138][139] The theory proposes an identity between consciousness and integrated information, with the latter item (denoted as Φ) defined mathematically and thus in principle measurable.

As will be illustrated below, IIT offers a way to analyze systems of mechanisms to determine if they are properly structured to give rise to consciousness, how much of it, and of which kind.

"[1] J. W. Dalton similarly criticized GWT on the grounds that it provides, at best, an account of the cognitive function of consciousness, and fails to explain its experiential aspect.