Thus far in Shakespeare's comedy, "Much Ado About Nothing," relationships are increasing in importance, and characters are going to outrageous lengths to pursue their love interests. Men like Benedick--the confident comic--utilize wit and boasting to attract the opposite sex (aka. Beatrice). However sometimes, more favorable ploys such as simply admitting outloud, or telling the truth, just don't seem to make progress. In those situations, lying comes into play, and there are certainly several situations where this is evident.
Claudio, the more sensitive and charming member of Don Pedro's army, returns to Messina with a newfound interest in Prince Leonato's daughter, Hero. This possible romance has mixed opinions, like critical Benedick's, and Don Pedro's encouragement. Yet Claudio can't seem to approach Hero himself. During the night of the masquerade, Don John (whom is aware of this situation) approaches Claudio and addresses him as Benedick. He exchanges his two cent on how Claudio is "no equal to his birth," and that he should "dissuade him from her" (II.1.162-163). In a soliloquy, Claudio says, "Thus answer I in the name of Benedick/But hear these ill news with the ears of Claudio" (II.1. 170-171). Without receiving this information, Claudio wouldn't have been aware of Don John's jealousy and cruelty, and the need to take caution if he wants to get ahold of Hero. This scene represents how lying in one's life can provide knowledge and keep one current on the latest gossip, but most importantly, its ability to help someone to protect themselves. In this case, the newfound knowledge does not harm anybody, but rather it assists somebody.
Another example arises in scene 3 of Act 2, where Don Pedro makes an attempt to bring Benedick and Beatrice together. This seemingly quarrelsome relationship has not developed yet, but while Benedick is hiding behind the bushes in the garden, Don Pedro lies about Beatrice's immense love for him, "By my troth lord, I cannot tell what to think about it, but that she loves him with an enraged affection, it is past the infinite of thought" (II.3.107-109). This very thought segues into Benedick's revealing speech where he addresses all of the emotions going through his mind. However, later, when Beatrice comes to invite Benedick in for supper, her abhorance returns, and it is evident that no such relationship exists yet. Lying can also, and more often, acheive un-favorable results; it can lead someone down the wrong path where they actually believe what is untrue. Benedick has the wrong impression, and now he will have to deal with Beatrice himself, and build a relationship without assitance. Perhaps by eliminating some of that superiority, and telling the truth, he will succeed.