Too much confidence can lead to errors during this distracting aspect. Overestimating a situation can lead to destruction and embarrassment.
Mercury square Jupiter natal gives a clever mind with a broad philosophical outlook on life. You have the potential to grasp abstract ideas and acquire a good understanding of any subject you wish to study. The only problem with this aspect of acquiring knowledge is sticking to your studies without being sidetracked. Concentration and self-discipline may hold you back from reaching your full intellectual potential.
For example, you may show promise and get off to a flying start at high school or university, but the lazy nature of Mercury square Jupiter could then see you slacken off, with a resulting drop in your grades. Sloppiness may apply not only to your thinking but all in your writing style or how you organize and plan other aspects of your life, such as filing or keeping up to date with bills and tax returns.