Human Brain in relation to my AI model

Artificial intelligence is not possible, because even a computer that rewrites its code will rewrite its code based on existing stimuli. This relates a computer's opinion to a human's opinion, which is seemingly random, but in fact, is not. My AI model echoes this.

In my AI model, we see that a dozen external stimuli cause a huge seemingly random result. It seems random, because a human cannot calculate a dozen or so mathematical equations to a million decimal places. When a computer "leans" towards an opinion instead of changing an opinion in binary steps, we get a far more diverse answer.

Imagine a tree, where every branch separates into two smaller branches. Take a bug, and start climbing to the top. After three levels, there are only eight branches our bug could have gotten to. Now take a bush, which has multiple branches at each level. By the time our bug gets to the third level, there are hundreds of different branches he can be on. Each branch represents a certain decision, or when applying it to computers, a variable.

My computer model of AI acts as the ladder, where the result is a lot less predictable. Similarly, the human brain uses this model, but with a many more branches. The brain acts like this computer program, with a finite amount of results from a finite amount of variables. However in the brain's case, you are dealing with more variables than you can possibly count on.

By using this model, this implies that Humans have a precisely predictable actions; only if, of course, we knew every single variable.