Gu Songyuan (Jingyuan) from Wumen was renowned in his youth for his scholarly achievements. Later, his father suffered from Rebing and was killed by a quack doctor who prescribed ginseng and aconite. This tragedy spurred Gu to abandon his studies and devote himself to medicine. For thirty years, he tirelessly pursued medical knowledge, and patients seeking his treatment came in droves. He once served in the Imperial Hospital but returned home to care for his aging parents. He authored the sixteen-volume "Medical Mirror." Once, he treated Wang Zangong, who was suffering from a seasonal febrile disease. Observing that the symptoms belonged to the yangming pattern, Gu prescribed White Tiger Decoction, using three taels of gypsum per dose. After two doses, the fever significantly subsided. A renowned elderly doctor in the region argued, "Profuse cold sweating, cold limbs, and hiccups indicate that only ginseng and aconite can restore yang." Other doctors agreed, clamoring that another dose of White Tiger Decoction would surely kill the patient. Gu, however, cited Zhang Zhongjing's statement, "When heat is extreme, the reversal is also extreme," and Yu Jiayan's assertion, "A yang syndrome suddenly turning into cold reversal is extremely rare," to argue his case. Despite his earnest efforts, the other doctors stubbornly refused to accept his reasoning. They administered ginseng and aconite to restore yang and stop sweating, but the sweating worsened, and the body grew colder. They then blamed the White Tiger Decoction, claiming that yang collapse was imminent and the situation was critical. The entire family was in a panic and returned to seek Gu's help. Gu persisted with the White Tiger Decoction, prescribing a large dose of three taels of gypsum. After two doses, the sweating ceased, and the body warmed. He then adjusted the decoction slightly, and after several doses, the patient fully recovered.