The primary idea that emerges from the disturbing mental images that haunt Mary Shelley after she overhears a discussion between Lord Byron and her husband is the implications of human power over life.
It is the talk between Lord Byron and her husband about whether the principles of life could be discovered and communicated that haunts her. They talked about Darwin's experiments and discoveries. When she goes to bed she dreams of a pale student, putting things together and the hideous phantasm of a man show signs of life. A human being could mock God's work! This scene she saw with shut eyes.
