However, the meaning of a metaphor can vary from culture to culture, region to region, and even from a rhetor to his audience. The rhetor must form an analogy that is both easy to identify yet not too blatant to produce an effective metaphor, and the audience must think beyond the literal definitions of the words before them to find the deeper inner meaning in a metaphorical phrase. Here, the Senate is a governing body comprised of many grown men, not a single orphan as it is being described. The phrase is merely stating that due to Cato's death, the Senate was left as helpless as an orphan. This leads us to the purpose of a metaphor.
Metaphors act as a sheperds to lead the audience onto the correct path of thought and mindset.
It does not leave all the work of persuasion to the rhetor himself. He can say a few words and allow the audience to ponder the metaphor and come to their own conclusions and hopefully the rhetor and his audience will meet in agreement about the meaning of the subject matter. Its use as an element of style , one of the five canons of rhetoric, can greatly enhance a rhetor's persuasive impact. A metaphor can prove to be effective where regular literal wording is not. In conclusion, to be a master of metaphor is to be able to read beyond the literal meaning of a phrase, and to be able to concoct one's own effective metaphors.