Horatio is an educated man and a skeptic. When Marcellus brings him along to the watch in Act 1, sc. 1, it is partly because of Horatio's educational background (Act 1, sc. 1. l. 46), but also partly because of his skepticism (Act 1, sc. 1. l. 33). Horatio attempts to practice the philosophy of stoicism, meaning he shows no emotion and is ruled instead by logic. Since the existence of ghosts defies logic, it is only fitting that Horatio should be brought along to the watch to see if the ghost appears. If Horatio sees it, it must exist. Horatio is also a loyal friend. He proves this when he tells Hamlet about seeing the ghost of King Hamlet (Act 1, sc. 2, l. 190) and when he swears to Hamlet he will not tell about what he's seen (Act 1, sc. 5, ll. 147-160). Polonius has a very high opinion of himself. He feels that he is in the know and is always right and that his words drip with wisdom and guidance. This is shown when he gives his parting advice to Laertes before Laertes goes back to school in France (Act 1, sc. 3, ll. 55-81). Polonius also likes to control situations by knowing what is going on with those around him, even if it means using deceit to find out information. Polonius told Ophelia to cut off her relationship with Hamlet at the end of Act 1, sc. 3. Then when Ophelia tells her father about Hamlet's disturbing behavior, Polonius instantly plans to tell the King that Hamlet is mad due to unrequited love and he has a plan to unearth proof of that, but that goes into Act 3. In Act 2, sc 2, Polonius tries to talk to Hamlet, convinced that Hamlet is mad, and he takes Hamlet's words to suit his own theory(Act 2, sc. 2, ll. 180-194). This shows how Polonius likes to be in control and how he believes that he has all the answers.