[dogscoff]

If an AI compares random numbers to decide whether to go left or right, is that free will? It will be chaotic and unpredictable...

Apply a force to a ball on a pool table- if the force and direction and locations of all the balls are known, the exact consequences can be predicted and known by applying a series of known physical laws. Once the force is applied, the rest of their movements could be said to be pre-determined by the laws of physics. Cause and effect.

Now consider that not only pool balls are subject to physical laws. People, cars, planets, atoms, brain cells... these are all made of matter and subject to the laws of physics. Therefore, if you apply a force to a car and all the variables are known, then the end result can be predicted. The implications of this are scary, and it's called determinism:

Determinism goes beyond "you're hungry and people eat when they are hungry, so I can predict that you will eat." It's more like "your decision to eat or not eat depends upon an immensely complex balance of psychological and physiological factors, all of which can be theoretically reduced to a bunch of chemicals and electrical impulse flying about in your brain and body."
Chemicals and impulses that are subject to the laws of physics, just like the pool table.

Imagine the universe as a massive, four (more?) dimensional pool table, with every one of the squillions of most fundamental subatomic particles as a pool ball. At the very beginning of the universe, in the instant that the big bang occurs, a force is applied. The qualities of that force set the entire universe in motion in a direction determined by the qualities (power, direction etc) of the force. Every movement of every atom from that moment until now, including the atoms in your brain clustered together right now in the right pattern to form the decision "I will eat" or "I will not eat"... every single movement in the entire universe is predetermined in just the same way the the balls on the pool table were. you have no free will. Your decisions are just cause-and-effect results of physical phenomena within your brain, which in turn are only the way they are because they were put there by other cause and effect reactions, and so on right to the big bang.

Now quantum mechanics provides us with a get out clause. QM implies that there are some things going on in the universe which don't necessarily have anything to do with cause and effect. They do not follow predictable laws, and there's room for free will again, although it implies some very wierd and unscientific things about the nature of the mind.

Anyway, I gotta go...