Many critics have commented on whether the creature in Frankenstein is a human being or not. If we analyze the development of the creature’s mind in terms of Hegelian development of human mind, we can approach the question more elaborately by showing which stage of development the creature reaches and which stage he tries, in vain, to reach. This article examines the creature’s mind at each stage as well as the strategy of exclusion corresponding to his development. The creature fails to be a rational creature because he cannot pass through the stage of self-consciousness, which the exclusion by human beings makes it impossible for him to achieve. But his failure paradoxically reveals the limitation of Enlightenment thinkers who confidently defined a human being as a rational creature. By standing for all aspects of a human being that cannot be incorporated into the category of a rational creature, the creature points to a hole in reality, that is, a human being.