An understanding of Nietzsche's work as a whole relies on a solid grasp of his views on truth and language, and his metaphysics and conception of the will to power. At the very bottom of Nietzsche's philosophy lies the conviction that the universe is in a constant state of change, and his hatred and disparagement of almost any position can be traced back to that position's temptation to look at the universe as fixed in one place. Nietzsche is skeptical of both language and "truth" because they are liable to adopt a fixed perspective toward things.
Words, unlike thoughts, are fixed. Our thoughts can flow and change just as things in the universe flow and change, but a word, once uttered, cannot be changed. Because language has this tendency toward fixity, it expresses the world in terms of facts and things, which has led philosophers to think of the world as fixed rather than fluid. A world of rigid facts can be spoken about definitively, which is the source of our conception of truth and other absolutes, such as God and morality.
Nietzsche sees the facts and things of traditional philosophy as far from rigid, and subject to all sorts of shifts and changes. He is particularly brilliant in analyzing morality, showing how our concept of "good," for instance, has had opposite meanings at different times. The underlying force driving all change is will, according to Nietzsche. In specific, all drives boil down to a will to power, a drive for freedom and domination over other things. The concept of "good" has had different meanings over time because different wills have come to appropriate the concept. Meaning and interpretation are merely signs that a will is operating on a concept.
Because facts and things depend for their meaning on ever-shifting and struggling wills, there is no such thing as one correct or absolute viewpoint. Every viewpoint is the expression of some will or other. Rather than try to talk about the "truth," we should try to remain as flexible as possible, looking at matters from as many different perspectives as possible. Nietzsche's ideal "philosophy of the future" is one that is free enough to shift perspectives and overturn the "truths" and other dogmas of rigid thinking. Such philosophy would see moral concepts such as "good" and "evil" as merely surfaces that have no inherent meaning; such philosophy would thus move "beyond good and evil." Nietzsche's ideal philosophers would also turn their will to power inward, struggling constantly against themselves to overcome their own prejudices and assumptions.
Nietzsche's unorthodox views on truth can help to explain his unusual style. Though we can follow trains of thought and make connections along the way, there is no single, linear argument that runs through the book. Because Nietzsche does not see the truth as a simple, two-dimensional picture, he cannot represent it accurately with a simple linear sketch. Nietzsche sees the world as complex and three-dimensional: more like a hologram than a two-dimensional picture. And just as a hologram is a three-dimensional image made up of infinitesimal two- dimensional fragments, each approximating the whole, Nietzsche presents his worldview in a series of two-dimensional aphorisms, each approximating a more complex worldview. Beyond Good and Evil is Nietzsche's perspectivism in practice: we can read every aphorism as one different perspective from which to look at Nietzsche's philosophy. There is some sort of line we can trace, moving from perspective to perspective, but essentially we end up with Nietzsche's philosophy in 9 big pieces and 296 smaller fragments. In this way, Nietzsche attempts to find the expression of his thoughts in language that best preserves their fluidity and three-dimensionality.