I do believe it was Magister D. Sass who wrote that mind, soul, and spirit are simply words humans use to describe our psychological and emotional lives.
I agree with his definition as far as Satanists are concerned.
If you are asking how the general public uses them, the nuances of the terms vary greatly. For example, "spirit" can be used to describe ambition and drive, but also nefarious demonic activity, depending on the context and/or the speaker's worldview.
Although, again from a Satanic worldview, ambition and drive ARE demonic!