I was recently introduced to an intriguing speech on the plausability of conscious machines given to a club of Objectivists a few years ago.
I appreciate many of the author's positions, but am not sure what his ultimate message is. The simple fact is that we are trying to recreate consciousness when we don't even know what consciousness is! Some attribute it to the soul, which doesn't address the issue and is simply an appeal to superstition. Others argue that thought is nothing more than calculation, but that fails to account for comprehension and understanding. Even though we are unsure of the direction we are going, we continue in our endeavor to build a thinking machine. In the end, perhaps our greatest success will not be the accomplishment of that goal, but in fact that we discovered the true nature of our own consciousness along the way.