This paper develops an empirically motivated theory of visual consciousness. It begins by outlining neuropsychological support for Jackendoff's (1987) hypothesis that visual consciousness involves mental representations at an intermediate level of processing. It then supplements that hypothesis with the further requirement that attention, which can come under the direction of high level representations, is also necessary for consciousness. The resulting theory is shown to have a number of philosophical consequences. If correct, higher-order thought accounts, the multiple drafts account, and the (...) widely held belief that sensation precedes perception will all be found wanting. The theory will also be used to illustrate and defend a methodology that fills the gulf between functionalists who ignore the brain and neural reductionists who repudiate functionalism. (shrink)

Many materialists believe that we should, in principle, be able to build a conscious computing machine. Others disagree. I favour a sceptical position, but of another variety. The problem isn't that it would be impossible to create a conscious computer. The problem is that we cannot know whether it is possible. There are principled reasons for thinking that we wouldn't ever be able to confirm that allegedly conscious computers were conscious. The proper stance on computational consciousness is agnosticism. Despite this (...) agnosticism, I think we are very close to understanding the material basis of consciousness. Close, but we will never get all the way there. Our understanding of the material basis of consciousness is ineluctably incomplete. That makes me a mysterian. But I am not a defeatist mysterian. I do not think the irresolvable mysteries of consciousness prevent us from formulating concrete empirically grounded theories of consciousness. I will even outline such a theory below. I also think we can identify some properties that are necessary for consciousness, and some that are sufficient. The problem is we cannot find properties that are both. This may sound like a contradiction, but it is not. We can know necessary properties and sufficient properties without knowing necessary and sufficient properties. One can know that drinking two litres of alcohol is sufficient for intoxication, and that at least one teaspoon of alcohol is necessary without knowing the quantity that is both necessary and sufficient. In the case of consciousness, the properties we know to be sufficient are properties that computers lack. The properties we know to be necessary can be possessed by computers, but we don't know whether those properties suffice. We can equip computers with every knowable necessary property and still scratch our heads when asked whether we have managed to create artificial experience. (shrink)

Gut Reactions is an interdisciplinary defense of the claim that emotions are perceptions of changes in the body.

Arien Mack and Irvin Rock make the radical claim that there is no conscious perception of the visual world without attention to it.

Can we make progress exploring consciousness? Or is it forever beyond human reach? In science we never know the ultimate outcome of the journey. We can only take whatever steps our current knowledge affords. This paper explores today's evidence from the viewpoint of Global Workspace theory. First, we ask what kind of evidence has the most direct bearing on the question. The answer given here is ‘contrastive analysis’ -- a set of paired comparisons between similar conscious and unconscious processes. This (...) body of evidence is already quite large, and constrains any possible theory . Because it involves both conscious and unconscious events, it deals directly with our own subjective experience, as anyone can tell by trying the demonstrations in this article. (shrink)