This soliloquy can be seen as presenting Macbeth as a tragic hero through the way that the dagger leads Macbeth towards Duncan's chamber and the murder he is going to commit. In a sense, Macbeth sees himself as almost being powerless to resist the dagger that he sees before him: he is a victim of forces beyond his control, whether they are supernatural or emerging from his own unconscious. Macbeth recognises this himself when he asks a series of questions to the dagger about its identity:
Art thou not, fatal vision, sensible
To feeling as to sight? Or art thou but
A dagger of the mind, a false creation,
Proceeding from the heat-opprest brain?
Macbeth seems to recognise that this dagger could be a result of his own fevered imaginings, but either way, he sees it guiding him towards the terrible crime he is about to commit, and he is a tragic hero in the way that he is unable to resist the dagger's lure and the way that it foreshadows both the blood he will shed with a real dagger and his own blood that will be shed by the close of the play. Macbeth is a tragic hero in this play because in this speech, by determining to kill Duncan, he sets himself on the path to perdition whilst seeming to be helpless to prevent this.