The more you look at the ascendant, the more mysterious it becomes. It’s what allows horoscopic astrology to be personal, the access point for our relationship with the heavenly spheres. In many ways it’s the crux of the whole field of horoscopic astrology (the word horoscope actually refers to the ascendant), but it’s a strange feature of the tradition. While the rest of the system describes the motion of powerful gods charged with overseeing fate, the ascendant is our tiny human life, and the techniques that rely on it let us peer into the will of God as it relates to the minutiae of that tiny life. But what does it actually describe? How is it different from either of the luminaries, both of which also have something to say about the self and the soul?
I think the answer is in the metaphors the ancients used for it. They called it breath, life, spirit, pneuma, and helm. In the hermetic cosmology of the first hellenistic astrologers, spirit or pneuma is the stuff that mediates between the divine soul and the earthly, fate-bound body. It mediates between our divine souls, the power we have as children of God, and our earthly bodies made by Nature in our image when we descended into the garden of materiality. The material world is bound by fate, and as long as we are here we need to obey its rules. Our bodies are how we interface with the world, and spirit is the substance through which our godlike souls unbound by fate interface with our bodies.
Not only is the ascendant a halfway point between the body and the soul, it is also halfway between fate and free will, in some sense. The metaphor of the helm or rudder of the ship here gives us another clue: the help is where decisions about where to go are made, where actions are taken in response to the waves, the wind, the ship itself. If we think of the ocean as fate itself— constantly shifting, teeming with life, possessing the power over life and death itself— the nautical metaphor becomes much more clear. That fate itself is the ocean, and as long as we sail on it in the form of our bodies, we are in many ways bound by its whims. But there is a big difference between a ship and a piece of driftwood. We are not helplessly floating on fate, we can steer the craft how we will.