Although I have used these ideas before, I think Daniel Kahneman (the psychologist who won a Nobel Peace Prize in Economics!) uses a set of descriptors that help distinguish and make clear the differences and traits of our "two systems".   (He writes about this in his brilliant work Thinking, Fast And Slow - A MUST to read, understand, and implement)


So, what I call the primitive system, where there is a mechanistic Dumb and Dumber representing the Monkey Mind and the Lizard Brain, he simply refers to those as System One. 

System One (or System I) is the system that is automatic and always looking out for danger signals in a way that has evolved to work (obviously it works, since we have survived and gotten better at it).  And it also is always automatically noting signals and then seeking to restore peace, calmness, and regularity so that our bodies and systems will function well. (The irony is that somehow our System Twos (System II) override this with behavior that induces system upset and keep us out of homeostasis, at great cost to ourselves.  But the System Twos can be used to re-decide and change this behavior.)

System One stores data and sets everything up so that what comes in triggers a process of prediction, so that we can anticipate and avoid dangers, and a process of pattern detection and matching with what could be dangerous and should be avoided.  It is very good at that.  (However, System Two is better at higher level decisionmaking and can be used to "work with" and alter System One 'errors' which occur from "thinking" too shallowly.)

System One is not, however, some mystical entity spouting off intuition that is somehow mysteriously correct, though it is effective in gathering information into a related whole.  System One is simply a mechanical miracle, functioning at the highest of any creature.


However, what made us survive the best, is the evolution of our System Two, which other animals do not have (at least not much comparatively).  It is the true "thinking" brain, with the ability to choose, design, discriminate, figure out, create, plan, anticipate more smartly, etc., so that we can do those things that have us survive much better.

And the reality of being human means that System One, which does not always make good choices but offers what makes life easier and quicker, will forever be active and not "overcomable"Doing battle with it (after all it is just a machine, and not a "spirit" of some self-agency) is not appropriate and not likely to yield very many victories.   Working "with" it, however, is eminently doable, to the extent that we can actually communicate with it and/or understand it. 

We System Twos (our higher brain) are the only ones that can establish the direction we want to go and then to direct the metaphorical workers in System One to get to work on it - but, I repeat, there is no magicalness to this, just wondrousness at the great machine.  

Note that when I say "we" or "I', I am referring to System Two, which is actually the "who" that we are.  (See Who I Am.)  Everything else is a support system.

As we all have heard, we can talk to our System One (unconscious, inner being...) and we can signal it with something to react to.  If we say "there is danger", it will react and go into automatic action.  If we say about the very same thing, and we reasonably believe it, "there is no danger", it will be calmed.  If we breathe deeply and slowly, it will be calmed.  The more we do "calming" things (meditation, relaxation, deep breathing [which signals "safety"], pausing, etc.) the more System One will "learn" to be calmer  and to be less hyper about potential danger - in fact, the brain will be rewired to screen out signals better and to be happier - automatically!!!!!   (See Rewiring The Brain.  Of course, read lots more than that, in the appropriate sections on this site, until you build up a working knowledge about how things work and what to do with that knowledge.)


We cannot overcome System One and it is a waste of time and energy to fight it.

We (System Two) can, however, work with it and direct it to some extent - and make a huge difference: the difference between a random, less fulfilling life and a directed, progressive, much happier life.

You will always be human, i.e. not perfectly functioning according to unreasonable expectations that we make up and then believe).  We cannot escape that, but we can work with it.  It is eminently useful and the most effective use of our time to learn how to work with it and then apply the techniques.  And that should be a top priority, as it is the quickest way to effectiveness in life, which allows you to create the happiest life.
The names I will use on this site

I can never remember which system is one or two, so I renamed them

1. Lower brain system (aka primitive mind system, monkey mind, Lennie)
Impulsive, efficient, crude, low discrimination ability

2. Higher brain system (Contains "consciousness", greater thinking ability, it is the You that experiences life.) Slower, more thinking, higher discrimination for better decisions and "design".

Further insight & understanding

Watch the Charlie Rose video of Daniel Kahneman on Thinking, Fast And Slow