As a student of the Jesuits who mastered Latin early, Baron Pierre de Coubertin was fond of drawing on the language of the ancients to fill his writing with wisdom.  This particular adage underscores one of his central tenets on the value of sport in modern society—the idea that the strength of the social fabric of any city or country would benefit from the robust health of its sporting citizens.  This quote is taken from “Olympic Letter XX,” which appeared in the Olympic Review in 1919.

“May youth not fail to haunt the factories of manly strength in which, according to the old adage, the strength of the city is forged. Civium vires hodie, cras civitatis vis. The strength which your sons acquire today will be the strength of your city tomorrow.”

Note: The gender bias of this quote, like so many from the Baron which are typically focused on young men, reflects the paternalism of the society he was raised in and his inability to break free of that sexist mindset despite his visionary brilliance in so many other areas. Fortunately, his heirs in the Olympic Movement eventually began to open the doors to full female participation—a process that continues to this day.