A comparison is a rhetorical or literary device in which two persons, places, objects, or ideas are compared or contrasted. Writers and poets use comparison to connect their emotions about something to something that readers may comprehend. Comparison can be used to emphasize the similarities between things that are different as well as their differences. Comparisons can also reveal more about the writer or poet than about the things being compared. For example, when Samuel Johnson described patriotism as "the last refuge of a scoundrel," he was using a comparison to explain why patriotism was so important to the nation. Without getting into too much detail, it can be said that England had been through many wars over the years and needed some way to keep itself together. Patriotism provided this need by keeping everyone united against their enemy. Another example would be Thomas Gray's poem "The Bard." In this poem, Gray compares the beauty of nature to the beauty of poetry. He does this by saying that both the bard and the natural world are beautiful but they are not like each other. The natural world is strong and powerful while the bard's words are weak and powerless. By comparing the two things, Gray is able to express how important poetry is to society and how necessary it is for people to listen to the bards' words. Finally, comparisons can be used as a tool for education.