Contrast
When the differences between two things are carefully enumerated the process is termed contrast. This is often used in combination with comparison, for no two things are exactly alike. They may resemble each other in nearly all respects, so comparison is possible and helpful up to a certain limit. To give an exact idea of the remainder the differences must be printed out; that requires contrast.
In contrast the opposing balance of details does not have to depend necessarily on a standard familiar to the audience. It may be an arrangement of opposite aspects of the same thing to bring out more vividly the understanding.
"This is often used in combination with comparison, for no two things are exactly alike."
In his History of the English People, Green explains the character of Queen Elizabeth by showing the contrasted elements she inherited from her mother, Anne Boleyn, and her father, Henry VIII. Such a method results not only in added clearness, but also in emphasis. The plan may call for half a paragraph on one side, the second half on the other; or it may cover two paragraphs or sections; or it may alternate with every detail—an affirmative balanced by a negative, followed at once by another pair of affirmative and negative, or statement and contrast, and so on until the end. The speaker must consider such possibilities of contrast, plan for his own, and indicate it in his brief.
Nearly any speech will provide illustrations of the methods of comparison and contrast. Burke's Conciliation with America has several passages of each.