Humanity’s Best Friend
Several times throughout the story, Griffin has what can be described as confrontations—or, at least, negative encounters—with dogs. In fact, he even admits at one point that “every dog that came in sight…was a terror to me.” With their reputation as man’s best friend and their primary job qualification in the world of humans being in the protective services field, the fact that even when they can’t see him, dogs are capable of sniffing out his sinister presence serves to implicate Griffin since his transformation into something unnatural, dangerous and even inhuman.
Griffin's Diaries
The packages that arrive for Griffin soon after he arrives at the inn are essential for his continuing experiments as he tries to figure out how to reverse the effects of invisibility. Everything about what he is doing in that room and those experiments are a complete mystery to the townspeople, but once he gets locked out and they get his hands on his diaries, they believe the mystery will start to clear. Instead, the diaries are written in secret code which actually turns out to be complicated mathematical formulas and foreign languages like Greek and Russian. The diaries thus become the central symbol of the educational gap between Griffin (and, later, Kemp) and the villagers with this ignorance gap itself standing in for a larger metaphorical statement about the class divide between laymen and scientific knowledge.
Food
One of the limitations of actually putting invisibility to use at will is that the processes of food digesting give Griffin’s presence away. Because he cannot eat at his leisure, food becomes a symbol of greed in place of money which in his state of invisibility almost becomes meaningless precisely because there is little obstruction to getting as much as he needs and because his needs are reduced as a result of the invisibility. The act of eating—which requires as much effort for him in his present state as earning money for most visible people—reveals the true motivation of greed for one person is often not one that is immediately visible to others.
Clothing
Griffin talks a lot about the struggles inherent in having to remain naked to remain completely unseen to the point that the struggle to find, use, and maintain clothing becomes a pervasive thorn in his side. At one point, he also admits that at the same time, clothes satisfy his immediate physical needs, it has the effect of undermining the very advantage of being invisible. Thus it is clothing—plain simple protective covering of the vulnerable human body against the elements—that becomes the novel’s dominant symbol of civilization. The difference between Griffin being able to interact at all with other people and being utterly isolated and alienated is the clothes which give his shape physical form.
Invisibility
Invisibility—the scientific fact of Griffin physically being in the presence of another, of touching and being touched by another, of speaking with another but of not being seen by another—becomes a symbol of existential alienation and societal rejection. Griffin is more than capable of making himself an outsider through his unpleasant personality, but the underlying message hints perhaps his inability to regain visibility is that he has fundamentally already been invisible to society precisely because he chose to chart the path of the social outcast To not be seen is portrayed as far different from not being felt or heard. To remain unseen is to stand outside the boundaries of human society; indeed, to be rejected as a candidate for entry. Griffin’s literal invisibility can be interpreted as symbolic of a figurative invisibility that had existed already, serving to form and shape the very personality which would seek to make the metaphorical become real.
