In his obsession with natural science, Victor Frankenstein becomes absorbed in a dangerous realm. For, to surpass what is natural is to venture into the desires reminiscent of Satan's in Paradise Lost in which he dreams of the new world to be created which he may make his own. Also, like the fallen angel in his desires, Victor is not content with the results "promised by the modern professors"; rather, he desires what "the masters of science" have--immortality and power.
This absorption of Victor into his insatiable desire to learn the wonders of science to the exclusion of his loved ones points to the unnaturalness of scienfific pursuit that the Romantics felt, for they were believers in intuition, the beauty and value of human friendships, and in the importance of family and loved ones. Moreover, Victor's obsession with natural science to the exclusion of personal relationships foreshadows the tragic events of Shelley's narrative.
When Victor begins to study chemistry (also referred to as natural science), his character becomes obsessive. He does not go home to Geneva but dedicates himself entirely, body and soul, to his studies. He believes that science, unlike other studies, offers constant enticements and "continual food for discovery and wonder." The more he learns, the more he wants to learn. He dedicates himself so fully to his studies that he makes rapid progress.
From his actions, it's clear that once he sets out to do something, he knows no moderation. He does not think about anything related to family or friends when he is in pursuit of scientific achievement, and there is nothing to temper his pursuit of this achievement. He thinks only of what he has yet to achieve, and he puts aside all the other considerations of life. His obsessive character and perfectionism show up in his studies.