There is one mistake we got to avoid, and that is the mistake of supposing that if you simulate it, you duplicate it. This is a deep mistake embedded in our popular culture - that simulation is equivalent to duplication, but of course it isn't. A perfect simulation of the brain - say, on a computer - would no longer thereby be conscious than a perfect simulation of a rainstorm on a weather-predicting computer will leave us all wet.

Descartes may have made a lot of mistakes, but he was right about this: you cannot doubt the existence of your own consciousness. That's the first feature of consciousness, it's real and irreducible. You cannot get rid of it by showing that it's an illusion in a way that you can with other standard illusions.

All of our conscious states, without exception, are caused by lower level neurobiological processes in the brain, and they are realized in the brain as higher level, or system features. It's about as mysterious as the liquidity of water, right? The liquidity is not an extra juice squirted out by the H2O molecules, it's a condition that the system is in; and just as the jar full of water can go from a liquid to solid, depending on the behavior of the molecules, so your brain can go from a state of being conscious to a state of being unconscious, depending on the behavior of the molecules. The famous mind body problem is that simple.

I have only one real message in this lecture, and that is: consciousness is a biological phenomenon, like photosynthesis, digestion, mitosis—you know all the biological phenomena—and once you accept that, most, if not all about the hard problems of consciousness simply evaporate.

We often attribute "understanding" and other cognitive predicates by metaphor and analogy to cars, adding machines, and other artifacts, but nothing is proved by such attributions.

There are clear cases in which "understanding" literally applies and clear cases in which it does not apply; and these two sorts of cases are all I need for this argument.

The sense in which an automatic door "understands instructions" from its photoelectric cell is not at all the sense in which I understand English.

Our tools are extensions of our purposes, and so we find it natural to make metaphorical attributions of intentionality to them; but I take it no philosophical ice is cut by such examples.

My car and my adding machine understand nothing: they are not in that line of business.

In many cases it is a matter for decision and not a simple matter of fact whether x understands y; and so on.