I attribute the quarrelsome nature of the Middle Ages young men entirely to the want of the soothing weed.

In this wry, anachronistic joke, Jerome suggests that the belligerence popularly associated with medieval youth could be “explained” by a modern comfort: tobacco. The humor depends on collapsing centuries—treating smoking as a civilizing, tempering habit whose absence made earlier generations more irritable and prone to quarrel. It also satirizes the tendency of armchair historians to offer single-cause explanations for complex social behavior, and it lightly mocks modern dependence on small indulgences to manage mood. The phrase “soothing weed” carries an ironic double edge: it sounds medicinal and calming, while also hinting at vice and self-deception.