Juliet is right! You don't have to use that system, that's just the one that most people are familiar with. Melody Kondrael posed the Spirit/Soul question in
this thread a couple of years ago. This was the response that Rwebhu's brother Sir Emeth Mimetes (aka the guy who introduced Essence Mapping to HW... and to an extent to the world) gave her.
Sir Emeth Mimetes wrote:
There are tons of different 'inner parts' to us. People have tried to define them in a dizzying array of often contradictory ways. It is a hard task.
There are also the Reins (in Hebrew it is the same word as 'kidneys'): which is more or less the throne of your decisions: your axioms and your assumptions.
There is your Heart: your meditator, the treasure where you store up good and bad things, where you draw from to provide strength in your actions.
There is your Brain: your physical thinker, when you memorize Scripture, you are not hiding it in your heart (you need to meditate on it to do that), you are storing it in your Brain. This is good, and very important, but not the same as meditating.
There is your Persona, or Personality: your makeup of emotional, physical, and mental (brain) preferences.
The difference between your Soul and Spirit is hard to define, because each has multiple meanings and uses, some of which overlap.
But there is your Nephesh life: you are alive. Animals have this too.
There is your individual Spirit: which goes to heaven and receives a glorified Body.
There are also terms which refer to two or more of these working in combination., such as your Will: the combination of your Heart and Reins.
That is the best I can do off the top of my head.
In a pm I asked how to apply this to essence mapping and his advice was that since there are so many confusing delineations of the "inner parts," we should use the ones that best suit the needs of your essence map.
On a more theological level, there are basically two schools of thought when it comes to the question of what we're made of. There's the dichotomous view which divides us into body and soul/spirit/mind. It kind of bundles together all the non-biological parts of us into one. Then there's the trichotomous view, which says we're made up of body, soul, and spirit. Generally in that view, the soul is equated with the mind and the spirit is the spiritual part of us. The soul is considered the center of thinking/reasoning (cognition), feelings/emotions, and decisions/willpower (volition). And the spirit is the part of us which senses spiritual realities (aka God and his Spirit). At least, I'm pretty sure that's the typical trichotomous view. It's the one I'm most familiar with.
But again, as Jay and Juliet have both said, use whatever you like and divide it up however works best for you. I think the reason the 4-part system was so popular is because in the beginning people learned Essence Mapping by basing their maps of the ones others had made and someone way back at the start used the 4-part system
I hope that doesn't confuse you.
However when it comes to 'mind', either that represents the intellect, knowledge, thought processes, etcetera of the person, or it represents all of that, and parts of what other people might classify under either soul or spirit, or all of the above and everything that other people might classify under soul or spirit. The last way is the way I usually use it. 