How does the language of the exchanges between Beatrice and Giovanni in the beginning of the story change compared to the way they talk to each other at the end of the story?

Giovanni is not what we originally see. Instead of a youth in love, he is merely overtaken with curiosity, lust, and vanity. In fact, his interest in Beatrice can, in a way, be compared to Rappaccini’s interest in science, and Baglioni’s interest in the old rules of medicine. All these men care for one thing, but in pursuing it, neglect its true foundation. Giovanni rashly lashes out at Beatrice, demonstrating that his love for her was ridden with doubt and distrust, demonstrating his own shallow and selfish nature. Rappaccini aims to protect his daughter, but in doing so, overlooks her personal interests. And Baglioni, while claiming to uphold the good rules of medicine that protect human life, invest suspicions into Giovanni’s mind and presents him with the very “medicine” that kills Beatrice, making him just as evil as Rappaccini in the end.