Retrograde planets
One thing in a chart talks about going back over ground, and it is also one of the things that gets explained worst: retrograde motion. This guide tries to set it straight.
A retrograde planet looks like it is moving backwards through the zodiac. It isn't. We watch it from an Earth that is moving too, and the effect is the one you get on a train when the carriage on the next platform seems to slide backwards while it is yours pulling away. Nothing odd happens in the sky. What does happen is that the planet slows down, lingers over the same stretch of zodiac and crosses it several times. In your birth chart that is neither a fault nor a weakness: it is a function that has turned inward. If you were born with Mercury retrograde, and roughly one person in ten is, your thinking sits more comfortably inside the process than inside the act of saying it out loud.
A retrograde planet does not tell you what is going to happen. It tells you how you move: where you double back before going on. The chapters look at the mechanism first, then at the retrograde stretches in the sky right now, Mercury included.