语本易经・说卦：“八卦相错，数往者顺，知来者逆。”指根据已过去的事来推测，就可预知未来。《明・陆容・菽园杂记・卷一》：“洪武中，朝廷访求通晓历数，数往知来，试无不验者，必封侯，食禄千五百石。”
英语 deduce what likely to happen in the future by reviewing what has taken place in the past
