What is Love?
In the 36 Lessons Vivec spends a lot of time trying to impress upon the reader how important it is to "know Love" and to "practice" it. But it immediately becomes apparent that Vivec's concept of Love is quite different from the traditional modern Western concept.
It didn't take much digging to discover that Vivec's Love is quite a lot like Aleister Crowley's Love, which is defined as any action or motion that is performed or experienced under Will.
So to explain Love we have to talk about Crowley's concept of Will.
This isn't a concept entirely specific to Crowley's work in Thelema, his system of spiritual philosophy, because it is mentioned on occasion in the 36 Lessons, even as early as Lesson 1:
'For I have crushed a world with my left hand,' he will say, 'but in my right hand is how it could have won against me. Love is under my will only.'
Thelema does not differentiate between an individual and God: "Every man and every woman is a star." The Lessons do not differentiate either. Vivec, Sotha Sil, Almalexia and Nerevar are all closely tied to the star symbol. In Sermon Two, Vivec is described as being star-shaped. In Sermon 36, those who looked upon Ayem are overcome by the meanings of the Stars. And Dagoth Ur promises that he brings a Star, which is himself. Within every person lies the divine, and the Lessons suggest that this is more evident in the powerful and the god-like. But it is obvious that the Lessons wish us to pursue our own Stars, which in turn is the pursuit of the divine in all of us.
"Will" is probably the most important concept in Thelemetic thought, and it is probably easiest to define it as the destiny particular to each and every individual. So it is suggested that a person acting in concert with that person's true Will is acting in a divine manner. Thus the most popular phrase of Thelema: "Do what thou wilt shall be the whole of the Law."
This is not "desire." Thelema does not encourage people to go around doing whatever they want. Instead, Will is only "in every way perfect" if it is unassuaged of purpose and delivered from the lust of result. Will must be done without mind or reason, as these are a hindrance to the will of the individual (and remember: every man and every woman is a star). And Will must be done without any desire for a result, because that desire clouds our judgment. Acting with (and not against) our Will requires a sort of void of mind, much like the void receptacle at the center of the promise of the wise.
Love is only true Love when it is "under Will." While Will is the Law, the nature of that Will is Love. It is the assimilation of experience, the bi-product of Will. While the Lessons offer very few examples of Love in an easy to discern form, Crowley gives us plenty of it. It is not what most people consider the act of loving someone emotionally, or kindness, or sentimentality. "Hate itself is almost like Love," writes Crowley. It is perhaps easy to think of Love as the joining of the enantiomorphic concepts of Nuit and Hadit, Crowley's terms for the immeasurable all-being (Nuit) and the infinitely small center point of everything (Hadit). Perhaps we can find a common theme with Anu and Padomay?
So, in summary: Love (when done under Will) is the assimilation of experience in accordance with the intrinsically divine nature of an individual; the act of progressively becoming one with our own Star.
Okay, now let's speculate: why Love?
To Love in Mundus means action with the goal of becoming divine. Vivec does not live in our world, a world where the conceptualization of the divine is difficult and obscure. It is not impossible for the average Elder Scrolls character to look divinity in the face, though it may take many forms. But Vivec suggests that every mortal can become divine by simply acting in accordance with their true divine nature, their Will.
In the Lessons, Vivec tells us: "Love is under my will only." But I think Vivec is also convinced, perhaps correctly, that his Will is the same Will as every other mortal in his domain. He fully possesses knowledge of the metaphysical structure of the entire span of existence, so perhaps he is correct. Or perhaps he believes that there are common events and activities all mortals must universally experience before they gain the wisdom to pursue their own Stars.
Before, we've all interpreted Vivec's actions in the Lessons as having an undertone of "this is for your own good." I think that's a simplification of this concept of Love. I strongly suspect Vivec intended to move the entire mortal existence forward, towards the Stars, even if he had to drag them kicking and screaming.