What major event in Victor's life has made him change his opinion about destiny and now consider chance?

This is largely in chapter 2. The question of the place of chance and destiny in Victor's fate also arises in this chapter. Victor "chances" upon the volume of Cornelius Agrippa; he suggests that he would never have become so fascinated with the alchemists if only his father had explained why their work was worthless. He also says that "destiny" brought him back to the study of natural philosophy: in this way, Victor attempts to absolve himself of culpability for his later actions.