Mercury in Capricorn: Themes, Strengths, and What It Tends to Mean
What Mercury signifies
Mercury is the kāraka of buddhi (intellect), speech, commerce, learning, and skilful communication.
Mercury in Capricorn
Capricorn is a earth, cardinal sign of responsibility, structure, and disciplined long-term effort, ruled by Saturn. Placed here, Mercury's significations tend to express through responsibility, structure, and disciplined long-term effort. This is a neutral dignity — the placement's expression depends on the rest of the chart, which is exactly what makes your own chart worth seeing.
How to read this
Treat this as a classical tendency, not a fixed verdict. The house this planet occupies, the aspects it receives, and the daśā period you are running all shape how it actually expresses — which is precisely why a generic sign reading can only take you so far, and your own chart says far more.