What is a good theme for the father-son antagonism in "Metamorphosis?"
Life at home, according to the story, is no paradise either. In particular, Gregor seems to have a difficult relationship with his father. The very first time Gregor's father is seen he is making a fist, albeit just to knock on Gregor's door. Soon after, however, he makes a fist more in earnest: when he first sees Gregor in his insect form, he shakes his fist at him and glares at him fiercely. Later he attacks him with a newspaper and a walking stick, and, later still, bombards him with apples, causing him serious injury. He is also not above making sarcastic comments, suggesting for instance that Gregor's room is untidy. And it turns out that he has deceived Gregor about the family finances, thus needlessly extending the length of Gregor's employment at the hateful travelling salesman's job. Finally, he does not seem particularly appreciative of the money Gregor has been bringing in; he is content to live off his son's labor, but Gregor feels there was "a special uprush of warm feeling'' about it.
Gregor's disappointment over the lack of appreciation is one of the few critical thoughts he thinks about his father. He also thinks briefly that the money his father hid from him could have been used to free him from his job sooner, but he quickly dismisses the thought by saying that no doubt his father knew best. In short, the antagonism as portrayed in the story is mostly one-way: the father abuses the son, but the son suppresses his angry responses and accepts his downtrodden state.