influences us to discover and communicate. Since its orbit around the sun is 9 mos compared to ours, every 3 months, Merc goes rx or travel backwards, just like it appears on a spinning hubcap.
Mercury is light, it's not much for "inner work"; being the ruler of Gemini, it's about "how the mind learn" and communicates. That's what obsesses all Geminis: how the mind works. It most important what sign it is in. That tells us how your mind works and the types of things you think of. All Mercurys are in the same sign as the Sun or next door.
I see no purpose when Mercury goes Rx. The reason I fight this is because: the old books talk heavily about planets being malefic or benefic. Mistakenly, people grossly overestimate Jupiter as a Great Benefit, when in fact there is a great downside to it - like economic collapse. Likewise, Saturn is unfairly classified as the Great Malefic, when nothing could be further from the truth. The truth with Saturn is that LIFE WILL FORM IN THE SHAPE (Since Saturn is the crystalizer) OF WHAT YOU OBSESS ABOUT MENTALLY. And most of us send many negative thoughts "out into the universe."
Therefore, I can see no positive purpose to Mercury Rx. Yet, I'm reluctant to see it, of all planets, as malific.
So, I keep researching. 
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