1. Because God gave us consciousness so we would have free will (spiritual dualism).
2. Because consciousness is a fundamental property of the universe (panpsychism).
3. Because consciousness developed as a side effect of the evolution by natural selection of complex cognition, e.g. language. Like mathematical ability, consciousness was not itself selected for, but developed along with other abilities that were selected for.
4. Because consciousness was selected for in evolution because it enhanced survival and reproduction of animals. Possible contributions to biological competitiveness:
5. Because consciousness developed when humans became literate and developed complex culture (Jaynes).
Panpsychism: all nature has a mental aspect. Consciousness is a truly fundamental feature of the world.
Science can not solve the problem of how physical stuff generates consciousness.
Quantum systems have noncausal but information-laden connections.
Consciousness is not reducible to physics, and does not emerge, so it must have already been present at lower levels. Chalmers needs an answer to the question of where mind came from.
From what we know of the the history of the universe, matter has been around for at least 15 billion years, but animal minds for only a few hundred million - consciousness has not been around for long.
Lack of simplicity: panpsychism requires postulation of both matter and mind.
How do quantum properties add up to our conscious experience? There still seems to be an explanatory gap.
Seager does not have a good reason for ruling out the emergence hypothesis.
The brain has entities (e.g. regions, neuronal groups, neurons, synapses, neurotransmitters).
The brain has activities (e.g. neuron firing, synchronized firing).
Synchronized firing is not an emergent property - it is not qualitatively different.
Hypothesis: consciousness is an emergent activity of particular kinds of synchronized neuronal firing.
For discussion of synchrony, binding, and consciousness, see the special issue of Consciousness and Cognition.
Note: the synchrony theory has mostly been applied to perceptual consciousness? What about emotional consciousness and self awareness?
The emergence of consciousness from neural activities is no more mysterious than the emergence of magnetic properties from atomic properties.
Excerpt from the Encyclopedia Brittanica:
All matter exhibits magnetic properties to some degree. When placed in an inhomogeneous field, matter is either attracted or repelled in the direction of the gradient of the field. This property is described by the magnetic susceptibility of the matter and depends on the degree of magnetization of the matter in the field. Magnetization depends on the size of the dipole moments of the atoms in a substance and the degree to which the dipole moments are aligned with respect to each other. Certain materials, such as iron, exhibit very strong magnetic properties because of the alignment of the magnetic moments of their atoms within certain small regions called domains. Under normal conditions, the various domains have fields that cancel, but they can be aligned with each other to produce extremely large magnetic fields. Various alloys, like NdFeB (an alloy of neodymium, iron, and boron), keep their domains aligned and are used to make permanent magnets.
1. With the origins of the universe (panpsychism)?
2. When simple brains evolved in worms and insects? Jellyfish have a nervous system but no brain.
3. When more complex brains evolved in vertebrates (e.g. fish) or mammals?
4. When language evolved in humans?
5. When human culture became literate?
Perhaps consciousness and its emergence are a matter of degree. E.g., dogs are conscious, but less so than people.
Summary of brain evolution.
Objection: Emergence does not close the explanatory gap. It does nothing to solve the hard problem.
Reply: There is no special explanatory gap. Explaining how consciousness emerges from brain mechanisms is just like explaining how magnetism emerges from electrical atomic mechanisms.
Objection: It's much simpler just to say that consciousness is a brain mechanism.
Reply: The properties of consciousness (e.g. qualia) are so novel compared to the properties of brains that it is more accurate to say that consciousness emerges.
Objection: Emergence is a mysterious notion, just like consciousness, and science should abandon them both.
Reply: Emergence, as understood by Humphreys, is not mysterious, and conscious experience is too real to be ignored.
Objection: Consciousness is a property of reality in general, not just brains.
Reply: See above.
For the emergence hypothesis to be convincing, however, there will need to be a much fuller description of the neural processes from which various kinds of consciousness (perceptual, emotional, etc.) emerge.
It is hard to find universal laws relating cognitive systems and conscious experience.
Non-cognitive systems might be proto-experiential, i. e. have very limited qualitative fields.
Conscious mental fields emerge from neural activities.
Chalmers' principle of coherence is trivial.
Chalmers' principle of organization invariance may be false - it needs experimental evidence.