Don't humans also follow pre-programmed instructions? The main difference is that human actions are just too complicated to be predicted exactly. A sufficiently large computer brain would be the same.
Well that's the question, do we follow pre-programmed rules? There seem to be to components to our minds, and I guess we could call them hardware and software. The hardware follows rules, chemical interactions, electrical signals etc. The software (consciousness, the soul, awareness, the mind, you can call it what you like) is an emergent property of the interactions in the hardware, and I don't think anyone really has a handle on how it works yet.
The software part seems to be more like a standing wave. It can't be seperated into distinct parts, it's the sum of all the interactions going on at the hardware level. Think of a simple oscilliscope, the wave you see is the result of all the values of all the different frequencies added together. Change a few of the frequencies and the entire wave changes. The brain is a lot more complex, obviously, but you get the idea.
A computer doesn't work the same way. In a computer the software is following rules, and the hardware is doing what it does as a result of those rules, while at the same time following its own rules (rules like capacitance, resistance and so on). Neither is an emergent property.
That's why I don't think we'll see AI developed in a single computer, or even a supercomputer, because a supercomputer is designed to act like one big computer. I think it's more likely we'll see it in a network of computers, like the internet, where emergence is possible.
Anyway, it's hard to explain where I'm coming from here. Either language is too clumsy or I'm just not good enough at using it.
edit - "But if, on the other hand, systems can have qualities not directly traceable to the system's components, but rather to how those components interact, and one is willing to accept that a system supervenes on its components, then it is difficult to account for an emergent property's cause. These new qualities are irreducible to the system's constituent parts (Laughlin 2005). The whole is greater than the sum of its parts. This view of emergence is called strong emergence. "
http://en.wikipedia.org/wiki/Emergence
That's what I was trying to say, the whole is greater than the sum of its parts. In a computer the whole is always just the sum of the parts.