贴切精当是设喻的起码要求。著名诗人艾青说过:“写作的时候,必须经过严肃的思考,注意使每句话,每一个比喻都能恰切地表达自己的思想和感情,弃绝浮华的词藻,力求朴素与纯真。”(《诗论·关于诗的一封信》)古代杰出的文艺理论家刘勰也指出:“比类虽繁,以切至为贵,若刻鹄类鹜,则无所取焉。”贴切精当是使比喻得以存在的基本条件。 Appropriate precision is the minimum requirement of metaphor. The famous poet Ai Qing said: “When writing, we must go through serious thinking and pay attention so that every word and every parable can express their thoughts and feelings exactly, reject the flashy words, and strive for simplicity and innocence.” (“A poetic letter on poetry”) Liu Xie, an outstanding literary theorist in ancient times, also pointed out: “If you compare more than one species, you will be as valuable as you are. If you engrave a class, you will have no alternative.” It is the basic condition for the existence of the metaphor.