Essential Energies
“Essence” is a complicated word in magical studies. It can mean “the type of esper associated with a certain emotion,” like the “essence of ambition” being choleric esper. It can also refer to the essence of a soul, which means any kind of esper that a human can naturally channel. Of course, since other souls can channel other sorts of esper, some use “essence” to refer to esper, which is pointlessly confusing since we’ve got enough definitions being bandied about and the word esper already exists. For purposes of this section of the text, “essence” is used to refer exclusively to a set of espers found in and spontaneously generated by the human soul (among others) which have certain elements in common with one another, especially the three lumen espers.
These five espers exist on a loose spectrum from light to dark (though all are invisible to the naked eye except when hyper concentrated): Agape, eros, philia, ether, and umbra. The first three are the lumen espers and are quite similar to one another, and it is actually a matter of some debate as to whether eros or philia are brighter than one another. Eros is defined by a softly fluctuating luminescence and mercurial nature, whereas philia is a steady light, dimmer than eros at its brightest and brighter than eros at its dimmest. Agape has the decency to be both steady and extremely bright.