One way to define madness is to say that madness is "a mental incapacity caused by an unmentionable injury." These injuries are not easy to see, but can appear in a time of stress. For instance, Hamlet has been in a state of mourning since his father died. Later he started acting crazy after he saw the ghost. Laertes was propelled into an angered state of madness after the death of his father. Ophelia had a unique form of madness. She seemed caught amid memories of her father and Hamlet. After what these three characters have endured life could never return to what it had been before.
Since the death of King Hamlet, young Hamlet appeared to be in a state of madness. This is seen in dialogue between Hamlet and Polonius when Hamlet questions Polonius by asking him "have you a daughter."(Act II, Sc.2, 199) Of course Hamlet knows Polonius has a daughter.
Hamlet appears to be mocking Polonius, where, in the past, Hamlet would have shown respect for him because of his age and his high position in the court. Later, Hamlet accuses Polonius of being the "Jephthah, judge of Israel,"(Act II, Sc.2, 427) when he tells Polonius that he thinks he would put his job in front of his daughter. Because of this Polonius thought Hamlet was mad because in the past Hamlet was well aware that Polonius cared for his daughter very much and would never put her second.
Unlike Hamlet, Laertes had developed a different kind of madness, a madness that was driven by rage. When talking to Claudius, Laertes became so enraged towards Hamlet that Laertes wanted to "cut his throat i' th' church."(Act 4,Sc.7, 144) Laertes' behavior was caused by the murder of his father, Polonius, and the drowning death of his sister,