impulsive（adj.）
15世纪初，最初指减轻肿胀或体液的医学用品，源于中世纪拉丁语 impulsivus，源自拉丁语 impuls-，其过去分词词干为 impellere，其含义为“撞击，推动”（见 impel）。指具有推动力、原因、能量等特性的人或事物来源于1600年左右。作为人类特征的“鲁莽、冲动的”一面，源于1847年，来自 impulse。早期就至少一次提到疯子：
The impulsive insane are often irritable, restless and jealous. Sometimes they have delusions, and sometimes not. Their delusions frequently seem to have no connection with their outbreaks of violence. They are often the best and at the same time the most dangerous class of patients in the asylums. They have little of the charity of the world, are most likely to be punished for their offences, and yet have the least control over their conduct. ["Impulsive and Homicidal Insanity," Boston Medical and Surgical Journal, April 19, 1843]
易冲动的疯子通常易怒、不安和嫉妒。有时他们有妄想，有时没有。他们的妄想经常似乎与他们的暴力爆发毫无关系。他们通常是医院中的最 best 也是最 most dangerous 的病人。他们缺乏对世界的宽容，极有可能因其行为而受到惩罚，但对其行为的控制最少。[“刺激性和凶杀疯狂”，波士顿医学和外科杂志，1843年4月19日]
该词起源时间：15世纪初