One of the phenomena which had peculiarly attracted my attention was the structure of the human frame, and, indeed, any animal endued with life. Whence, I often asked myself, did the principle of life proceed? It was a bold question, and one which has ever been considered as a mystery; yet with how many things are we upon the brink of becoming acquainted, if cowardice or carelessness did not restrain our inquiries. I revolved these circumstances in my mind and determined thenceforth to apply myself more particularly to those branches of natural philosophy which relate to physiology. Unless I had been animated by an almost supernatural enthusiasm, my application to this study would have been irksome and almost intolerable. To examine the causes of life, we must first have recourse to death. I became acquainted with the science of anatomy, but this was not sufficient; I must also observe the natural decay and corruption of the human body. […] Now I was led to examine the cause and progress of this decay and forced to spend days and nights in vaults and charnel-houses. My attention was fixed upon every object the most insupportable to the delicacy of the human feelings. I saw how the fine form of man was degraded and wasted; I beheld the corruption of death succeed to the blooming cheek of life; I saw how the worm inherited the wonders of the eye and brain. I paused, examining and analysing all the minutiae of causation, as exemplified in the change from life to death, and death to life, until from the midst of this darkness a sudden light broke in upon me—a light so brilliant and wondrous, yet so simple, that while I became dizzy with the immensity of the prospect which it illustrated, I was surprised that among so many men of genius who had directed their inquiries towards the same science, that I alone should be reserved to discover so astonishing a secret.

Basic set up:

In this excerpt, the scientist Victor Frankenstein explains how his obsession with finding the source of life developed.

Victors Frankenstein in Mary Shelley's novel is obsessed with figuring out how to create life. And he arrives at that secret by focusing on the study of anatomy and physiology.

This passage is a great example of the way in which sci-fi treats science (and technology) as major themes. They don't call it science fiction for nothing, after all. Here, Frankenstein tells us in detail how his obsession with finding the secret of life grew, and how his study of anatomy and physiology led him to unlock that secret. The scientific emphasis of the passage, in other words, reflects just how central this theme this is in Shelley's novel.

By having this novel narrated in the first person, through Frankenstein's perspective, Mary Shelley has us really enter into the scientific mindset. In the excerpt above, we really feel Frankenstein's enthusiasm for his study.

He describes to us how he was animated by an almost "supernatural enthusiasm" for his subject, and how one step led him to another. In telling us about his scientific quest, Frankenstein sweeps us readers along with him, so that we too become interested in his discovery.