The character of Hamlet exhibits a great deal of interiority, meaning he reflects deeply on the meaning of life. For this reason, he has often been called the first modern hero.
Through him, the play explores the meaning of life. As the play opens, Hamlet's entire world has been upended. His beloved father is dead, his mother has rapidly remarried his uncle (a man Hamlet despises), and the two seem determined to thwart his desire to grieve. To make everything worse, Hamlet meets his father's ghost and learns that Claudius murdered his father. The ghost directs Hamlet to avenge his death.
From this point on, Hamlet is besieged with questions of meaning. What is his purpose? He doesn't want to be alive in a world in which a brother is capable of murdering a brother to get his throne; he also doesn't want to be an agent of revenge. He doesn't even know whether the ghost is really his father or an agent of Satan tempting him to kill an innocent man. Why has his world become so dark? Is it better to be alive or be dead? Hamlet dreams of suicide as a way out of his pain and seemingly overwhelming problems. But is that really better than life? What if he goes to hell?
The human condition refers to the questions we all ask about our lives—and Hamlet, as noted above, asks many of these. He also asks: Why is the world so evil? Why does Denmark seem so rotten and cancerous? Why are we born if we are just going to die? he wonders as he looks at Yorick's skull. How do we know what is true? If caught between two ethical systems, how do we decide what to do? Should Hamlet adhere to the bloodthirsty revenge ethic that requires a son to avenge his father or to the Christian ethic of forgiveness? Is Fortinbras right to march an army into Denmark and risk so many lives to recapture a few feet of soil?
Hamlet struggles with all of these until the end of the play. At that point, believing he was providentially saved from death in England, he comes to trust that God has the universe firmly under control, and that he, Hamlet will die when it is his time. This allows him to face his end—as well as his task of killing Claudius—with equanimity.