This essay discusses Goethe's inaccurate definition of a soul and how a new definition makes Hamlet a "soul unfit" for revenge

Johann Wolfgang von Goethe's Wilhelm Meister's Apprenticeship explores Shakespeare's Hamlet through analyses of its characters, but most of all through an examination of the main character and his soul. Goethe inaccurately defines a person's soul as their underlying nature, which one infers remains static regardless of the events that occur during one's lifetime. However, when one looks at Hamlet throughout the play, his central character, which is comprised of his emotional and moral nature, is …

…life make him intensely affect him. He contemplates suicide, and he is also unable to overcome his morals, kill his uncle, and attain his revenge until he is practically forced to do so by circumstance in the final scene of the play. Because of his unsteady emotional and moral nature that are dangling drastically close to falling into actual insanity, Hamlet is in no state to undertake the task of revenge that he is given.