Impressions: Hot head; quick to react; speaking before thinking; physical stress linked to self-expression; fear of provoking strong reactions; self-censorship; contentious; threatened when proven wrong; speaking mind is cathartic; communiques push into new ground; energized 'messenger.'Pre-loaded Mercury
When Mercury squares Mars in the birth chart, the messenger is pre-loaded. Intense. Edgy. There's raw brilliance that pushes against the barriers of the mind. Some natives use that sharpened sword to wound in aggressive debates. Others might push to champion a cause, or create a searing vision as an artist.
Mercury here has a spring set by Mars, making the native an unpredictable communicator. A quick-to-react mind has a lot of physical force riding in with it. This is someone with the potential to pound fists on the table, when making a point. Or hurl objects. Others might sense this and avoid topics that set things off.
A square here puts up a challenge to resolve the mind's perceptions in all their nuance, with the superfast urge to act of Mars. First reactions can later be seen in a different light. By working the muscles of perception, and trusting all your intelligences in the moment, Mars has more freedom to strike while the iron is hot!Energized Intellect
Some fear can come up, to resolve the square by speaking (even though afraid of what it will release). There's potential to be someone who holds others with rapt attention, because they sense that as the wheels turn, sparks are flying! This native can end up a dynamic speaker who by showing courage, pushes into new ground.
A challenge is to get away from turning every conversation into a fight. There's a gift here, though in being quick on the draw. Some with this aspect, according to Stephen Arroyo, have good hand-eye coordination, as "conscious mind blends with physical energy, stimulating both powerfully -- an energized intellect."
If others are dull-eyed and stuck in thought loops, you're there to urge movement. If you've got this in your birth chart, you're a potentially inspiring instigator. You rouse people out of their mentally sleepy state, in the workplace or as part of a movement. Your words bring out the fight in others, and get them moving!