This is an aspect of nervous activity and some self-doubt. The person will often question and is never too sure of his or her feelings about people and ideas. The heart and the head seem to be in constant conflict. The person seems to constantly trying to rationalize one'a activities and sentiments. A great restlessness and frequent changes of residence also categorize this influence.
Head and heart can be in constant conflict within you; decisions may be made according to which is dominant at any given time. This temporary supremacy can vary, like a pendulum movement, and may also be related to the sign, house, and element that each planet is in. It may be that one planet consistently dominates, and the other one becomes repressed. If Mercury dominates, then the Moon activity can sink deeper into the unconscious mind, influencing you more subtly and pervaisvely from a hidden position where the emotional coloration is less noticeable to you than to others. If Mercury is repressed, then rationality and logic may diminish, and choices may be influenced by insistent emotions, instincts, and feelings; habit patterns may often be security-biased. Sometimes you may observe that, when attempting to restore inner balance, Mercury begins to excessively rationalize feelings and emotions. If this is allowed to persist, you may start to deny the validity of your emotions and feelings, and in so doing repress your Moon sensitivity, creating another imbalance.
Your mom likes to pick up fights over how certain things were supposed to be done better and differently. Then you start to think about how is she doing things and what’s wrong with that. And this is how an endless war starts. Verbally, you are never good enough for each other.Later in life, when you are in the relationship the partner keeps asking you: “Who cares how it’s done. It just needs to be done and that’s it. Why complicate?” and it’s such a long story.
I have found that this aspect can suggest sleep problems, there are tensions in expressing emotions. But again you have not really given enough information in fact only 1/3 of the information.
The other two thirds are the planets in signs, planets in houses and its with the whole chart that synthesis begins.
“Moon square or opposition Mercury There is a conflict here between the head and the heart. The emotions tell them one thing and the mind tells them something else. The result is a wavering, and a see-saw effect is most evident with the opposition—emotional to the point of irrationality at one moment, and logical the next. How to blend the head and the heart is a constant struggle for these individuals, usually because there is a tendency to resist blending them!
These people love to chat, enjoy story-telling and writing/poetry, and usually possess a sparkling wit! They are animated when they speak, and have a sense of humor that others appreciate simply because it’s very imaginative. Some are especially adept at satire. You can usually tell their moods by how much they’re talking. When nervous or excitable, they talk up a storm. Moodiness is a characteristic, definitely, and an especially subjective nature makes them prone to hypersensitivity. It usually has to do with the fact that they take in so very much from their environment. This is also one of the reasons why they tend to be indecisive. While Mercury conjunct Moon people tend to be quite consistently rational, the hard aspects of Moon-Mercury generate a swing between irrational and rational thoughts and feelings. This rarely transfers into action, however. It’s pretty much something that takes place “upstairs” in the mind, although others are sure to see the struggle from time to time. These people are always interesting, and usually funny. They have a tendency to misrepresent themselves with what they say from time to time, but they’re charming, if a little kooky, friends.“ http://www.cafeastrology.com/natal/moonmercuryaspects.html
“Moon square Mercury The square formed between the Moon and Mercury suggests conflict between your mind and your emotions. You have difficulties making reasonable judgments because your feelings get in the way. Irrational decisions place you at odds with people sometimes, and you have the feeling that you’re being treated unfairly when this may not be the case. You dwell on trivial personal matters and may have a real sense of insecurity. You can communicate well with those that are very close to you. Yet your peer group outside the family can be a problem with which you must deal before you can achieve success. Avoid the tendency to discredit the ideas of others when they disagree with your ideas or challenge you. Try to evaluate the ideas of others in an objective and quiet manner” http://www.skyscript.co.uk/moonaspects.html#mosme
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