Without even understanding dichotomy, writers use it consistently in works where a sharp contrast is required. This is because dichotomy is a useful literary device which creates drama, causes conflict and adds depth to characters and situations. To simplify it it is useful to consider the conflict, for example, between good and evil, a popular literary theme.
Shakespeare uses dichotomy in his complex characters. Macbeth is a good example of the conflict between good and evil as Macbeth, rewarded for valor on the battlefield and considered the king's loyal ally, cannot fight his "vaulting" ambition which, he admits, "o'er leaps itself" and to which he refers in Act I, scene vii, line 27. Macbeth has the power to discount the witches' prophesies but, instead, due to his tragic flaw and his over-zealous wife, he transforms into a killing machine, callously attempting to dispose of anyone in his way.
Macbeth also contains the famous "foul and fair" analogy which first appears in line 10 of Act I, scene i. Despite the uncertainty that surrounds these words, as they forewarn the audience of what may follow, dichotomy is apparent in the struggle between the natural and the supernatural which would have attracted Shakespearean audiences who were both fascinated and terrified by it. There is a definite conflict between the Christian values of the audience and their superstitions and obsession with witchcraft. In Act II, scene iv, line 41, the audience is warned of those who "would make good of bad, and friends of foes."
Dichotomy is represented in Lord of The Flies by the democracy and order of the conch contrasted with the savagery of Jack and his hunters. Ralph and Jack reflect two opposing sides of the leadership struggle, despite the fact that they both have certain characteristics which could have, under different circumstances, complemented each other. By the end of the novel, however, the situation has changed and the dichotomy between good and evil is uncertain as the reader sees the change in Ralph who cries, "for the end of innocence."