Non-existence

[Edwardo Piet]

But that doesn't prove a neccessary causal link exists between brain activity and consciousness generally

It doesn't need to. There's not even any self-evidence of consciousness as a phenonmenon in itself. I have self-evidence that I'm conscious, and my consciousness changes when I get, for example - hit on the head and knocked unconscious. There's no evidence for consciousness existing as a phenomenon seperate to the brain. And whether the brain is 'all consciousness' or 'all mind', is just semantic babbling because it makes no actual difference to our experience of this world, and there's no evidence of any difference actually existing.

While it's true that philosophical zombies grants the existence of the brain and exactly uses the brain as the explanation for everyone elses behaviour, that is because philosophical zombies is a realist ontology, which is far more complex than solipsism which acknowledges the existence of nothing beyond nor outside of the conscious experience of sense-data, and since all knowlege we have about the brain (in that scenario) is based on conscious experience of sense-data, it is not sufficient to refute solipsism to speak of the brain, something whose existence the solipsist does not acknowledge.

But if the concept of p-zeds is incoherent then other people have consciousnesses too, seperate to mine - otherwise I'd be conscious of them. So other minds exist apart from mine, and thus solipsism is erroneous.

EvF