Let’s start with a different case. When you see a mountain, you see an object miles away, even though the visual experience is in your brain. The mountain doesn’t have to go into your brain (thank goodness) in order for you to see it, because the brain can represent the external object.The case of the pain in your hand is not exactly the same, but here too it seems that one thing (in your head) is representing another thing (in your hand). Perhaps it is stranger to suppose that we represent something outside our head as having pain that that we represent something outside our head as having the shape of a mountain, but something like that seems to be what is going on. And this may seem less strange in light of the fact that we know anyway that we have the power to represent things that aren’t actually there, for example in a case of hallucination. So the fact that the pain isn’t actually in our hand does not mean we can’t perceive it as being in our hand.I don’t want to sound complacent. ...

You could have had lots of conscious experiences yesterday that you forget today. What makes an experience conscious is its character at the time, not the traces it leaves in memory. This raises the tantalising question of how you know that you haven’t had all kinds of wild experiences in the past that that you have forgotten. This is an interesting inversion of more familiar sceptical arguments, which tend to assume that we do know about our experiences but question how we can know what caused them.It seems clear that I do have reason to believe that I have had some experiences I now forget. After all, I have reason to believe that my memory is very imperfect. For example, I have reason to believe that I had many more experiences as a child than I can now recall. At the same time, there are lots of crazy possible experiences that I have reason to believe I never had. In many cases, the fact that I don’t remember having an experience makes it pretty likely that I didn’t have...

The nub of Searle's provocative argument is the claim that if you are given only symbols, without being told their meaning, plus rules for manipulating those symbols to generate an output of symbols, where those rules never talk about meaning, then you are never going to learn the meaning of those symbols, however intelligent the output seems to those who do know their meaning. Computers (at least traditional ones) seem like that: they are symbol manipulating machines who never work with meanings, only 'shapes' (or patterns of electrical impulse). The argument has considerable force, but it raises an obvious question: what could we have that computers don't that enables us to wring meaning out of the mere sound waves and electromagnetic radiation that our senses detect?

Jackson argues that even if you had complete physical knowledge of some conscious state -- such as the sensation of a color or a sound -- that you had never experienced --say because you were color blind, or deaf --you would still learn something new about that sensation if you went on to enjoy it yourself. Since you already knew all the physical facts about that experience and you learned new facts about it when you had the experience, there must be non-physical facts about it for you to have learned. You make a legitimate response to this argument by questioning the assumption that you would learn something new if you had complete physical knowledge. Who knows? But I confess that I don't find this reply entirely satisfying. Although complete physical knowledge is a very different from our actual situation, I am moved by the fact that as I learn more purely physical facts about sensations these seem to tell me nothing about what experiencing that sensation is like, what it feels like,...