Note 2 — V. Human Life; its various Relations and Conditions
H. W. (Henry William) Auden translation
The first meaning of exercere is to keep in motion, give no rest to. Then, metaphorically, to keep busy, to harass—e.g. fortuna aliquem vehementer exercet. Lastly, exercere is used to express the main activity in any branch of industry, thus, exercere agros, to farm; metalla, to carry on a mining industry; navem, to fit out ships, be a shipowner; vectigalia, to levy, collect taxes, used specially of the publicani; qui exercet iudicium, the presiding judge (praetor).