Mercury is the fastest-moving planet in the solar system, and in astrology it governs the quickest faculty we have: the mind. It rules how we think, how we talk, how we write, and how we learn. Mercury is not interested in depth for its own sake — it moves laterally, making connections, trading information, finding patterns, and expressing ideas. Ruling both Gemini and Virgo, and the third and sixth houses, Mercury covers two complementary modes of mind: the curious, social intelligence of Gemini and the precise, analytical intellect of Virgo. In the third house, Mercury governs everyday communication, your local environment, siblings, and the flow of information. In the sixth house, it rules craft, critical thinking, work routines, and health habits shaped by the mind. Mercury retrograde — which happens three times a year for about three weeks each — is when the planet appears to move backward from Earth's perspective. This is when communication breaks down, technology glitches, travel delays pile up, and misunderstandings multiply. It is also an excellent time to review, revise, and reconsider — all activities that begin with the prefix "re-."