Question

I saw in Derekh HaChayim by the Maharal (on the Mishnah of Shimon the Righteous) that he proposes an idea like this: not that there are only two normative systems (between a person and his fellow, and between a person and God), but that in addition to those two there is a third one—between a person and himself. The principle is clear and based on a familiar thesis: a human being is made up of a material, animalistic part and an intellectual, spiritual part, and there is value in “developing” the spiritual part, which is done through Torah study; and likewise there is value in detaching from the material part. (Of course, by the word “development” I do not mean developing intellectual skills, but rather something more along the lines of bringing a person toward spirituality and away from materiality.)
A. Does the Rabbi think there is real substance to this thesis?
B. If so, what could be the reason that there is normative value in “developing the spiritual part”? It is easy to understand intuitively what is good about helping others and about doing the will of the Holy One, blessed be He, but what could be the logic of “developing the spiritual part” for the sake of the person himself? After all, if you asked a person what he wants for his own good, he would say something like: to enjoy life, not to develop the spiritual part within him.