A person is truly mad if they do not get their veins bled in this season, when a river of blood surges from the vein of every flower branch.

This couplet captures the fierce, intoxicating madness of spring, where blooming red roses are imagined as nature's own veins bursting with blood. In classical medicine, bloodletting was used to cool the heat of passion or delirium, but the poet turns that logic on its head. He suggests that when nature itself is pulsing with such intense life, anyone who fails to surrender to this wild frenzy and open their heart to passion is the one truly out of their mind.