the Hard problem of consciousness

The hard problem of consciousness is the problem of explaining how and why sentient organisms have qualia[note 1] or phenomenal experiences—how and why it is that some internal states are felt states, such as heat or pain, rather than unfelt states, as in a thermostat or a toaster.[2] The philosopher David Chalmers, who introduced the term “hard problem” of consciousness,[3] contrasts this with the “easy problems” of explaining the ability to discriminate, integrate information, report mental states, focus attention, and so forth.[4] Easy problems are (relatively) easy because all that is required for their solution is to specify a mechanism that can perform the function.[4] That is, regardless of how complex or poorly understood the phenomena of the easy problems may be, they can eventually be understood by relying entirely on standard scientific methodologies.[4] Chalmers claims that the problem of experience is distinct from this set and will “persist even when the performance of all the relevant functions is explained”.[4]

The existence of a “hard problem” is controversial. It has been accepted by philosophers of mind such as Joseph Levine,[5] Colin McGinn,[6] and Ned Block[7] and cognitive neuroscientists such as Francisco Varela,[8] Giulio Tononi,[9][10] and Christof Koch,[9][10] but disputed by philosophers of mind such as Daniel Dennett,[11] Massimo Pigliucci,[12] and Keith Frankish[13] and cognitive neuroscientists such as Stanislas Dehaene,[14] Bernard Baars,[15] and Antonio Damasio.

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Prof. Donald Hoffman gves an interesting perspective on the ‘hard problem’ in his work on Conscious Agent Theory: see also:/prof-donald-hoffman-on-conscious-agent-theory