Macbeth is introduced in the play as a warrior hero, whose fame on the battlefield wins him great honor from the king. Essentially, though, he is a human being whose private ambitions are made clear to the audience through his asides and soliloquies (solo speeches). These often conflict with the opinion others have of him, which he describes as "golden" (I:7, 33). Despite his fearless character in battle, Macbeth is concerned by the prophecies of the Witches, and his thoughts remain confused, both before, during, and after his murder of King Duncan. When Duncan announces that he intends the kingdom to pass to his son Malcolm, Macbeth appears frustrated. When he is about to commit the murder, he undergoes terrible pangs of conscience. Macbeth is at his most human and sympathetic when his manliness is mocked and demeaned by his wife (see in particular Act I, Scene 7).
However, by Act III, Scene 2, Macbeth has resolved himself into a far more stereotypical villain and asserts his manliness over that of his wife. His ambition now begins to spur him toward further terrible deeds, and he starts to disregard and even to challenge Fate and Fortune. Each successive murder reduces his human characteristics still further, until he appears to be the more dominant partner in the marriage. Nevertheless, the new-found resolve, which causes Macbeth to "wade" onward into his self-created river of blood (Act III, Scene 4), is persistently alarmed by supernatural events. The appearance of Banquo's ghost, in particular, causes him to swing from one state of mind to another until he is no longer sure of what is and "what is not" (I:3,142).
But Macbeth's hubris or excessive pride is now his dominant character trait. This feature of his personality is well presented in Act IV, Scene 1, when he revisits the Witches of his own accord. His boldness and impression of personal invincibility mark him out for a tragic fall.