The mechanism of the Action Potential sounds very reasonable and rational enough. However, it is difficult to comprehend exactly how does a sequence of action potentials actually translates into such complicated processes as feelings, thoughts, decisions, beliefs, movements etc...

Yes, we can claim to understand the core mechanism of the action potentials and, therefore, the nervous impulse, but how can it be all that is behind "us"? It is difficult to think of us in terms of just ‘computer’ programs in which the existence of the concentration gradients in the environment of a specific axon is all that is responsible for the incredibly broad range of the possible behaviors. I do understand that we possess a great number of greatly different neurons so there are a lot of possible combinations of possible concentration gradients. Yet, are there really enough possibilities to result in so many various behaviors? It seems to me that there is an infinite number of behaviors but there is a finite (a very large, but yet, finite) number of the possible combinations of concentration gradients and their possible locations. So how can there be a relationship between these?

The complexity of the "program" that translates an infinite number of inputs into a finite number of possible concentration gradients, which it then translates into an infinite number of outputs is just incredible. And it does not even run out of memory. Or does it? Maybe we forget things because the "computer" decided that we don’t need that specific memory anymore and translated something more important over it. Will we ever know?

An interesting way to think of it. Perhaps, though, you're using too much of a computer metaphor. There isn't so much a program which translates inputs into gradients, as a set of gradients and permeabilities which is both the translator and its product. Similarly, there isn't so much a distinct program and memory as a single thing which serves the functions of both. A finite number of states (possible gradients and combinations)? Hmmm. Not sure. That one I have to think about more. PG