秦二世时，丞相赵高野心勃勃，日夜盘算着要篡夺皇位。可朝中大臣有多少人能听他摆布，有多少人反对他，他心中没底。于是，他想了一个办法，准备试一试自己的威信，同时也可以摸清敢于反对他的人。
一天上朝时，赵高让人牵来一只鹿，满脸堆笑地对秦二世说：陛下，我献给您一匹好马。秦二世一看，心想：这哪里是马，这分明是一只鹿嘛！便笑着对赵高说：丞相搞错了，这里一只鹿，你怎么说是马呢？赵高面不改色心不跳地说：请陛下看清楚，这的确是一匹千里马。秦二世又看了看那只鹿，将信将疑地说：马的头上怎么会长角呢？赵高一转身，用手指着众大臣，大声说：陛下如果不信我的话，可以问问众位大臣。
大臣们都被赵高的一派胡言搞得不知所措，私下里嘀咕：这个赵高搞什么名堂？是鹿是马这不是明摆着吗！当看到赵高脸上露出阴险的笑容，两只眼睛骨碌碌轮流地盯着赵高脸上露出阴险的笑容，两只眼睛骨碌碌轮流地盯着每个人的时候，大臣们忽然明白了他的用意。
一些胆小又有正义感的人都低下头，不敢说话，因为说假话，对不起自己的良心，说真话又怕日后被赵高所害。有些正直的人，坚持认为是说明书而不是马。还有一些平时就紧跟赵高的奸佞之人立刻表示拥护赵高的说法，对皇上说，这确是一匹千里马！
事后，赵高通过各种手段把那些不顺从自己的正直大臣纷纷治罪，甚至满门抄斩。
故事出自《史记·秦始皇本纪》。成语指鹿为马比喻故意颠倒是非，混淆黑白。
calling a stag a horse
in the reign of emperor the second of the qin dynasty (221-207 b.c.), the prime minister zhao gao, obsessed with ambitions, was planning to usurp the throne day and night. but he did not know how many of the ministers in the court were allowed to be ordered about by him and how many of them were his opponents. so he thought out a way to test how high his prestige among the ministers was and also to find out who dared to oppose him. one day when court was held, zhao gao let someone bring a stag to the court and, with a broad smile on his face, he said to emperor the second of the qin dynasty:"your majesty, here is a fine horse im presenting to you." looking at the animal, emperor the second thought that it was obviously a stag and that it couldnt be a horse. so he said smilingly to zhao gao:"mister prime minister, you are wrong. this is a stay. why do you say it is a horse?" remaining calm, zhao gao said:"will your majesty please see more clearly? this really is a horse that covers a thousand li a day." filled with suspicion, emperor the second looked at the stag again and said:"how can the antlers be grown on the head of a horse?" turning around and pointing his finger at the ministers, zhao gao said in a loud voice:"if our majesty do not believe me, you can ask the ministers." the nonsense of zhao gao made the ministers totally at a lose, and they whispered to themselves: what tricks was zhao gao playing? was it not obvious whether it was a stag or a horse? but when they saw the sinister smile on zhao gaos face and his two rolling eyes which were gazing at each of them, they suddenly understood his evil intentions. some of the ministers who were timid and yet had a sense of right eousness did not dare to say anything, because to tell lies would make their conscience uneasy and to tell the truth would mean that they would be persecuted by zhao gao later. some ministers with a sense of justice persisted that it was a stag and not a horse. there were still some crafty and fawning ministers who followed zhao gao closely in ordinary times. they immediately voiced their support to zhao gao, saying to the emperor:"this really in a horse that covers a thousand li a day." after the event, zhao gao punished by various means those ministers with a sense of justice who were not obedient to him, even with whole families of some of those ministers executed. this story appears in "the life of the first emperor of the qin dynasty" in the historical records written by sima qian. from this story people have derived the set phrase "calling a stag a horse" to mean deliberately misrepresenting some thing and misleading the public.
