also keep in mind that the progression of computer intelligence will sneak up on us. over the next several decades, machine competence will rival - and ultimately surpass - any particular human skill one cares to cite.
as computers achieve a comparable - and greater - level of complexity, and as they are increasingly derived at least in part from models of human intelligence, they, too, will necessarily utilize goals with implicit values and emotions, although not necessarily the same values and emotions as humans exhibit.
a variety of philosophical questions will emerge. are computers thinking, or are they just calculating? conversely, are human beings thinking, or are they just calculating? the human brain follows the laws of physics, so it must be a machine, albeit a very complex one. is there an inherent difference between human thinking and machine thinking?
to pose this question another way, once computers are as complex as the human brain, and can match the human brain in subtlety and complexity in thought, are we to consider them conscious?