The Australian philosopher David Chalmers (1966— ) is best known for his work in philosophy of mind. He is a professor at the Australian National University.

Chalmers first addresses the difference between the two types of problems in the science of the mind. The easy problems, he says, are the ones that have to do with how the brain functions and handles specific tasks. The hard problem, however, is how and why the brain gives rise to consciousness at all. Although many theories address the weak problems, Chalmers does not agree that the hard problem is addressed at all by the scientific community.

He then argues for a version of property dualism. In making is his point, Chalmers invokes the Mary’s Room thought experiment from Frank Jackson. He supposes that if someone (Mary, in the example) spends her whole life without seeing colour, yet learns all of the physical and neurological facts about it, she still learns something new about colour when she sees it for the first time with her own eyes.

Chalmers believes that this argument proves the existence of a non-physical fact about consciousness. Therefore, there must be something beyond the physical world as it is known that must account for consciousness. He points out that physics attempts to provide a “theory of everything”, but it will continually fail to do so as long as it fails to include consciousness in its considerations.

As with previous unexplained phenomena, Chalmers supposes that the solution is to add a fundamental feature in order to close the explanatory gap between physics and consciousness. He argues that there must be some new mental properties, what he calls “psychophysical laws”, that must be accounted for, and that those properties must not be reducible to the physical properties of the brain.

Chalmers doesn”t suppose to know what those things are, however. He speculates that it may be the case that information theory will come into play — that information-bearing systems give rise to a certain experiential property. The more complex the system, the greater that experiential property becomes, until it becomes conscious.

A potential problem with this speculation, which Chalmers acknowledges, is that it may imply the consciousness of things that we would not normally consider to have consciousness at all. For instance, Chalmers wonders if this means that a thermostat may have some experiential properties, even if they are especially dull. He does not commit to the notion that they do, but the possibility remains in the more speculative area of his thought.

Selected Works

• The Conscious Mind: In Search of a Fundamental Theory (1996)
• “The Puzzle of Conscious Experience” (1995)