My attention was fixed upon every object the most insupportable to the delicacy of the human feelings. (Shelley, 1961, p. 44) Frankenstein challenges the values of man that are based on fear and thus goes forward to create a beast that even Dante could not have conceived of. (Shelley, 1961, p. 50) He then chases the beast to his own death.

The Beast on the other hand exemplifies a helpless child in many ways, resenting the fact of his own existence and vilifying his maker for having made him without thought of what a lonely and destructive life he would face.

You, who call Frankenstein your friend, seem to have a knowledge of my crimes and his misfortunes. But in the detail which he gave you of them he could not sum up the hours and months of misery which I endured, wasting in impotent passions. For while I destroyed his hopes, I did not satisfy my own desires. They were for ever ardent and craving; still I desired love and fellowship, and I was still spurned. Was there...

188)
The Beast is the expression of progress gone to far, and without the thought of morality that should be given to any creation of life.

The novel operates on all levels of horror, terror, horror and revulsion, as each character that faces the Beast does so with the extreme fear of the unknown (terror) the physical and psychological fear of the possibilities that such a beast might exhibit (horror) and revulsion as his physical appearance was revolting to all who saw him. Each of these levels of horror are exemplified as expressions of real human fear but is especially empathetic to the human fear of the unknown. No human living gives the Beast the real opportunity of knowing his character, beyond the fear that he represents.

References

Shelley, M.W. (1961). Frankenstein or, the Modern Prometheus. New York: Collier Books.