• David J Chalmers

  • Discussion on the so-called Hard Problem of Consciousness

  • Dividing what is called consciousness into two categories:

    • Psychological consciousness: publicly accessible descriptions of consciousness, such as its neurochemical correlates or its role in influencing behavior.
    • Phenomenal consciousness: experience; something is phenomenologically conscious if it feels like something to be it.
  • While it may be possible to demonstrate the former, doing so does not necessarily indicate the latter.

Summary of the Introduction:

The author aims to develop an understanding of consciousness that respects it, aligns with science, and regards it as a natural occurrence governed by natural laws. This leads to conclusions that some may find anti-scientific, such as the belief that consciousness cannot be fully explained in physical terms and that a form of dualism holds true. However, the author argues that these positions are necessary for a complete understanding of consciousness.

A comprehensive theory of consciousness must not be reductive. Key elements of such a theory involve recognizing the connections between consciousness and cognitive processes, viewing consciousness as an “organizational invariant” stemming from specific functional organizations, and exploring the links between consciousness and information.

Quoted text: Discussion on the Approach:

  • It is easy to claim that consciousness is an illusion or does not exist, but since we typically perceive ourselves as conscious in our daily lives, such a claim is not made here.
    • The easiest way to develop a “theory” of consciousness is to deny its existence, or to redefine the phenomenon in need of explanation as something it is not.

      • Indeed
    • This usually leads to an elegant theory, but the problem does not go away. Throughout this book, I have assumed that consciousness exists, and that to redefine the problem as that of explaining how certain cognitive or behavioral functions are performed is unacceptable. This is what I mean by taking consciousness seriously. Some say that consciousness is an “illusion,” but I have little idea what this could even mean. It seems to me that we are surer of the existence of conscious experience than we are of anything else in the world.

  • Striving to construct a scientific theory in relation to nature
    • The third constraint is that I take consciousness to be a natural phenomenon, falling under the sway of natural laws. If so, then there should be some correct scientific theory of consciousness, whether or not we can arrive at such a theory.

    • However, it concludes that a reductionist or materialistic approach cannot be taken.

Chapter 2:

  • What does it mean for a phenomenon to be reductively explained or to be physical? This chapter provides an explanation, focusing on the concept of supervenience. It argues that while almost everything in the world can likely be reductively explained, consciousness may be an exception.

    • Review of reductionism
    • Supervenience
      • Supervenience
      • In general usage, supervenience often involves discussing the dependence of mental properties (propositional attitudes or qualia) as property 2 on physical states of the brain (neuronal states, concentrations of neurotransmitters). It is used to argue that mental properties arise entirely dependent on physical states of the brain, meaning that “mental properties are supervenient on physical states of the brain.” This essentially means that ‘for any possible situation, with different mental properties, the same physical state of the brain will not be present.’

      • The crucial point is that 1 cannot be reduced to 2, which is important.
        • But what is the difference between reduction and supervenience?