The problem
You flinch at "spiritual," or you flinch at "data." Both flinches close the book.
The shelf is crowded with two kinds of failure. On one side, teachers who loot the vocabulary of quantum physics to sell certainty they have not earned, promising healing frequencies and thoughts that order from the universe's catalog. On the other, a skepticism so total that it throws out a genuine practice along with the false promises attached to it. Between the believer who swallows everything and the scoffer who spits out everything, the sincere reader is left without a guide.
You have observed your own moods swing, your attention sharpen and dissolve, your energy climb through a morning and drain by afternoon. None of it is mystical. What is rare is a way to treat these movements as material that can be studied and refined, with the skeptic's standards and the contemplative's discipline both kept intact.