Mary Shelley conceived of Frankenstein at a time when science, the modern representative of reason, was moving toward world-making and away from its traditional world-representing role. The more powerful applied reason became, the more creative became the rationalists’ work. Dr. Frankenstein marks the moment when the work of reason threatened itself with success. Mary Shelley’s novel stands as a living critique of pure reason, in which the very power of human reason undermines its claim to address a single reality, unchanged by the manipulations of individual consciousness. In its Romantic fervor, Frankenstein announces a new stage in the very old history of creation, a paradoxical stage we still stride, where growing anxieties about determinism accompany growing suspicions that human subjectivity, whether exercised by poet or scientist, is the sole determinant of reality.
The whole of the essay is really worth reading, and I find the contrast with other critiques of the place in which the novel stands for or against science to be very much in its favor. What gives Frankenstein its power is the sort of prophetic role it has in seeing the great power which science would later assume.
I was reminded a Stephen Jay Gould essay (collected in Dinosaur in a Haystack) that decried the later interpretations of Frankenstein as a novel about scientific hubris. He focused on how the "monster" transformed from Shelley's erudite, feeling creation to the lumbering patchwork ogre of Karloff. In it, there was some talk about the general move, especially in film, towards such depictions of science as ready to kill us all. (More fruitfully, he applied the contrast to that between the book Jurassic Park and its film.) Gould's critique seems a little flat to me, looking back on it, but it was really influential in how I saw the literary treatment of scientific progress as a teenager.
In the end, Gould saw a conflict between narratives where human fobiles undo scientific progress's promise and those where the progress itself was evil. It is easy to try to project either view onto Shelley's novel, and I find that the New Atlantis piece finds an interesting middle-way. Unfortunately there is no discussion of the novel's subtitle–"the Modern Prometheus"–as the figure of Prometheus is a strange juxtaposition to the Dr. Frankenstein it describes. Gould would have us see Frankenstein as a Prometheus undone by personal evil (which, for a man who was never quite separate from his parents's Marxism, often has some sort of economic underpinning), while Kessler's essay would find the figure of Prometheus as an uneasy fit to the novel's moral universe. (Perhaps the scholars see the subtitle as one of the suggestions of Mr. Shelley, but I am not that educated on the novel.)
The freshest (to me) part of the essay is the discussion of Frankenstein's creation as suffering from the same dreads as all creations; he turns the "monster" into a sort of existential everyman. This is a rewarding turn of thought, and I leave it to you.