To me, the most important message in this book is that nature is superior to science and that there are things that human beings should not try to do. I think this message is gotten across quite well by the subtitle of the book.
Victor should never have tried to give life to the monster. Giving of life is something that only God/nature can do. When he tried to do this, he broke the natural order and he ended up paying the price for his mistake.
I think that the message of the book is that people should not try to violate this natural order that exists. It is a warning against trusting too much in science.
Numerous issues are revealed in Shelley's Frankenstein. The enotes Study Guide on the novel lists these themes:
- Alienation and Loneliness
- Nature vs. Nurture
- Appearances vs. Reality
- Duty and Responsibility
- Justice vs. Injustice
- Forbidden Knowledge
- Science vs. Nature
- Multiple Personalities
Of these, I suggest the most important issues in the novel are:
Science vs. Nature: This is at the heart of the work, and is timely when applied to Shelley's time period. Science goes too far and is irresponsible.
Alienation and Loneliness: both Victor and his monster, in the end at least, suffer alienation and loneliness.
Nature vs. Nurture: left on his own, the monster, as he is referred to by Victor, truly becomes one.
Frankensteinis actually a very complicated but wonderful novel. It is much deeper than it appears. Several of the issues within the novel are as follows.
Playing God- Victor was driven by ambition and the loss of his mother to create a perfect human being. He wanted to be the creator.
Parent/Child- Victor represents the father to his creation. he rejects his creation causing him a great deal of emotional pain.
Human vs. Inhuman- The theory as to what constitutes a human being is represented through the creature being brought to life made from parts of a human but not having a real birth or the things that make a human come to be.
Self-Guilt- Victor eventually carries the guilt for having made the creature but it is not towards the creature but for the life and loved ones he lost.