All understanding can be interpreted in terms of process, mode and direction.
The two fundamental processes of understanding are the unconscious and conscious respectively.
Holistic (synthetic) knowledge is based (directly) on the unconscious, whereas partial (analytical) knowledge is based (directly) on the conscious.
The two fundamental modes of understanding are the cognitive and affective which are initially closely related with conscious and unconscious respectively.
Rational (impersonal) knowledge is based directly on the cognitive mode and emotional (sense) knowledge based (directly) on the affective mode.
The two fundamental directions of understanding are the external and internal respectively.
Objective knowledge relates (directly) to the external direction; subjective knowledge relates (directly) to the internal direction.
In dynamic mathematical terms, conscious and unconscious processes are "finite" and "transfinite" with respect to each other.
In like manner cognitive and affective modes are "real" and "imaginary" with respect to each other.
Finally, external and internal directions are "positive" and "negative" with respect to each other.
Initially, all these directions are considerably confused in experience. The linear level is concerned with the explicit differentiation of direction (only) whereby the external is separated from internal and literally posited in experience.
The linear level is thereby one directional (dimensional) in nature.