张元素年少习儒，八岁便应童子举，二十七岁参加进士考试时，因文中触犯了朝廷避讳的字而落第——这场意外的挫折，让他转而弃仕从医。他后来提出"脏腑辨证""药物归经""引经报使"等理论，为中药的临床应用建立了一套系统的辨证框架，是易水学派的开创者。他的两位学生李杲、王好古，都曾"以千金为贽"正式拜师，可见其在当时医界的声望。

Zhang Yuansu studied the Confucian classics from childhood and sat for the imperial examination at twenty-seven, only to be disqualified for inadvertently using a character that violated an imperial naming taboo. This setback led him to abandon officialdom for medicine. He went on to develop the theories of viscera-based diagnosis, herb-organ meridian tropism, and "guiding herbs," building a systematic framework for the clinical use of Chinese medicine, and founded the Yishui school. His two students, Li Gao and Wang Haogu, are recorded as having paid substantial tuition to formally study under him — a mark of his standing among physicians of his time.