How is deception a theme of Much Ado About Nothing?

Shakespeare explores, among other things, the positive and negative effects of deception in Much Ado About Nothing. On the positive side, Don Pedro, with help from Claudio, Leonato, and Hero, plans to bring Benedick and Beatrice together in love through a complicated deception. He obviously believes that the war between the two is based on their hidden feelings—in other words, their love is hiding behind their pride. This drives the first half of the play. The second half, however, is centered on deception whose end is to destroy happiness and reputation: Don John and his cohorts try to ruin both Claudio's and Hero's lives, as well as the lives of those surrounding the two. That the play turns out positively is good—after all, this is a comedy—but Shakespeare's point in his use of deception is that it can be used to further human relationships in a positive way just as it can be used to destroy relationships. In the case of Much Ado, deception can go hand-in-hand with both comedy and tragedy.