Victor views his switch from science to math as the intervention of a guardian angel.
Perhaps one of the reasons that Victor was successful in creating his monster is that he had knowledge of many subject areas.
As a teenager, Victor, his “passions vehement,” was highly interested in studying science because he wanted to learn “the secrets of heaven and earth” (ch 2, p. 8). His father seems to have left him to decide what to study and comments occasionally, but does not really guide him. When Victor see s a lightning bolt strike a tree, he becomes interested in natural phenomena.
In this mood of mind I betook myself to the mathematics, and the branches of study appertaining to that science, as being built upon secure foundations, and so worthy of my consideration. (ch 2, p. 20)
Young Victor might not have known what was in store for him, but since the book is essentially a biographical flashback the adult Victor reflects on this time in his life as one of the happiest, later being miserable due to his creation. Victor describes this “almost miraculous change of inclination and will” as the influence of a “guardian angel.”
….the last effort made by the spirit of preservation to avert the storm that was even then hanging in the stars, and ready to envelope me. (ch 2, p. 20)
The adult Victor is reflecting on how close he came a normal life, and to averting the tragedy caused by his creating the monster. Unfortunately, the change does not last. Victor of course becomes interested in medicine.
It was a strong effort of the spirit of good; but it was ineffectual. Destiny was too potent, and her immutable laws had decreed my utter and terrible destruction. (ch 2, p. 20)
Victor attributes the change to his angel, but the change back to destiny. Apparently, the intervention of his guardian angel was short-lived. He continues on the path to destruction, or at least that is how he sees it looking back on an adult.
This is one of the most interesting sections in the book, because the young Victor seems to have had to go back rather far to find a happy time. He also has pinpointed the one time in his life when he might have gone on another course, and sees himself as being pulled along by destiny. He created the monster because he was destined to do so. By saying this, Victor is limiting the responsibility he himself takes for his mistakes.