He lies to her telling her that Hamlet does not love her, he only lusts for her, in truth he does love her: "Ay, springes to catch woodcocks. I do know, When the blood burns , how prodigal the soul- (1.3.115). Through the play Polonius hides behind his mask appearing to be a honest loving parent. In reality Polonius lies, manipulates people and eavesdrops on peoples conversation, hence him hiding behind Gertrudes clothing. Polonius helps contribute to the theme appearance verses reality by showing how his appearance is not his true nature, behind the mask there lies someone totally different.
Horatio is the one significant character at the end of the play, chosen to reveal to the world the real "story" (5.2.321) of the events in and around the Danish court. This last demand of the tragic hero implies the view of Horatio as a man of moral integrity and honesty. This thought is also based on some of his replies to the protagonist. "I came to see your father's funeral" (1.2.176) is the direct and clear answer to Hamlet's question about the reason for his visit. And again in the last scene of the first act, he honestly tells the Prince of Denmark about his "wild and whirling words" (1.5.133), without holding back or making any other unnecessary comment. Another aspect, underlining his credibility becomes obvious in Hamlet's plan to catch the King. Horatio's "I did very well note him" (1.2.274), is enough for Hamlet to go on with his revenge plan. And besides the prince also the older soldiers call out for his experience and knowledge as a scholar, which is a remarkable sign for his reliability. Against these passages, his description of the ghost appears more dubious. In his first attempt to convince Hamlet about the ghost's very nature, he said, he saw Hamlet's father "once" (1.2.186). Then only a few lines later he states that he can identify the Old King as good as his own "hands" (1.2.212). Though weighed against the other points, this argument cannot diminish Horatio's trustworthiness.