A diagram showing the relationship
between various views concerning
the relationship between
consciousness and the physical
world
impossible within the bounds of nature but possible within the bounds of logic.[47] This would imply that
facts about experience are not logically entailed by the "physical" facts. Therefore, consciousness is
irreducible. In Chalmers' words, "after God (hypothetically) created the world, he had more work to
do."[48] Daniel Dennett, a philosopher of mind, criticised the field's use of "the zombie hunch" which he
deems an "embarrassment"[49] that ought to "be dropped like a hot potato".[29]
The knowledge argument, also known as Mary's Room, is another common thought experiment: A
hypothetical neuroscientist named Mary has lived her whole life in a black-and-white room and has never
seen colour before. She also happens to know everything there is to know about the brain and colour
perception.[50] Chalmers believes[48] that when Mary sees the colour red for the first time, she gains new
knowledge — the knowledge of "what red looks like" — which is distinct from, and irreducible to, her
prior physical knowledge of the brain or visual system. A stronger form of the knowledge argument[50]
claims not merely that Mary would lack subjective knowledge of "what red looks like," but that she
would lack knowledge of an objective fact about the world: namely, "what red looks like," a non-physical
fact that can be learned only through direct experience (qualia). Others, such as Thomas Nagel, take a
"physicalist" position, disagree with the argument in its stronger and/or weaker forms.[50] 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."[31] The knowledge argument implies that such a language could not
exist.
David Chalmers' formulation of the hard problem of consciousness provoked considerable debate within
philosophy of mind, as well as scientific research.[43]
The hard problem is considered a problem primarily for
physicalist views of the mind (the view that the mind is a physical
object or process), since physical explanations tend to be
functional, or structural. Because of this, some physicalists have
responded to the hard problem by seeking to show that it dissolves
upon analysis. 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). A third response has been to accept the hard problem as
real but deny human cognitive faculties can solve it.
PhilPapers is an organization that archives academic philosophy
papers and periodically surveys professional philosophers about their views. It can be used to gauge
professional attitudes towards the hard problem. As of the 2020 survey results, it seems that the majority
of philosophers (62.42%) agree that the hard problem is real, with a substantial minority that disagrees
(29.76%).[25]
Knowledge argument
Philosophical responses