There isn’t much talk in Freemasonry of the equinoxes. It’s all about the solstices, starting, even, with an allusion during the First Degree—as another dichotomic pair, like checkered pavement, directional opposites, twin pillars, spirit and matter, and other contrasts balanced for harmony.

Robert Louis Stevenson is said to have been a Brother Mason in Scotland. My query via social media to the Grand Lodge there went unrequited, but in his Strange Case of Dr. Jekyll and Mr. Hyde, he delves very much into paradoxical human nature: good versus evil; public versus private; civilization versus barbarism. Just as we do in our lodges.
From Stevenson’s novella: “I learned to recognize the thorough and primitive duality of man; I saw that, of the two natures that contended in the field of my consciousness, even if I could rightly be said to be either, it was only because I was radically both.”
And so it goes in our initiatic rituals. Darkness overcome by Light at first; Ignorance cleansed by Knowledge in the second; and Death defeated by Eternal Life in the Sublime Degree. We can’t have one without the other in the perpetual labor.