Aizen has a very descriptive style that focuses heavily on painting a vivid livable image in the minds of his readers. He wants to make sure the worlds he creates feel real and tangible from the perspective of anybody who picks up any one of his books.
Aizen writes strictly in first-person. For the simple reason of immersion. First-person allows for the reader to feel as if they are the main character, and he wants them to experience every moment with their very eyes.
From metaphysics, to quantum physics, Aizen draws from what's he's interested in to supply his novels with interesting details. Keep an eye out for Easter Eggs and religious symbolism as well!
Why does he write what he writes? Why does he bother to push philosophy when some might say it's a dying subject in a world of mindlessness. He does it for that very reason. Aizen believes the world needs more philosophy. More knowledge of self. And that's precisely what his novels aim to accomplish. One by one, every novel that is written has a lesson to teach. And it is usually aimed at the ideas surrounding self worth and self discovery.
He is a firm believer in the idea that introspection holds the key to unlocking the mysteries within one's self. It can lead to healing. And in turn lead to greatness.