"Smith is an intelligent creature with the ancestry of a man, but he is more Martian than man. Until we came along he had never laid eyes on a man. He thinks like a Martian, feels like a Martian […] He's a man by ancestry, a Martian by environment." (3.15)
Mike identifies himself as a Martian because he was raised on Mars. Basing identity on place of origin is hugely important to many characters in the novel—like Kansas Duke. How about you? What do you base your identity on? Other than being a Shmooper, of course.
"Well, if it ain't 'Dimples!' [Jill] Hi, honey, what brings you here?" (4.3)
Jill's nicknames start out cutesy like 'Dimples' and evolve to stuff like 'little brother' (not quite as cutesy). By the time she's the high priestess, her nicknames are associated with gods. If you like where this conversation is headed, check out the Names section of "Character Clues" for further discussion.
"I do not know," Smith answered slowly. "How does woman look? What makes you woman?" (4.40)
Mike stumbles on a great conundrum of identity. What makes a woman a woman and, likewise, a man a man? Is it social roles, biology, a choice of sexuality? Take your pick.
I am only an egg. (5.118)
Here's Mike's self-recognized identity. While the world knows him as the Man from Mars, he understands himself as only a young Martian in need of guidance and maturity.
"A poisonous snake is not dangerous, no more than a loaded gun is dangerous—in each case, you must handle it properly." (13.41).
Jubal did not label his pet snake as dangerous, so for him, it wasn't. According to Jubal, labeling can sometimes inform identity rather than come out of it. P.S. Poisonous snakes are dangerous.
"Man is the animal who laughs." (14.159)
Amen. And notice how this steers clear of issues of biology and social ordering. When Mike laughs later in the novel, it proves another important coming-of-age for him, the age when he becomes a full-on human. Welcome to humanity, Mike—buckle your seatbelt, it's going to be a bumpy ride.
Smith knew that shape was never a prime determinant; it was necessary to go beyond shape to essence in order to grok. (15.36)
This is one of the very few specific details we get about how to grok in the novel. The shape of something will give clues to its identity—in this case a gun—but it won't give you the identity as a whole.
"The faith in which I was brought up assured me that I was better than other people; I was 'saved,' they were 'damned'—we were in a state of grace and the rest were 'heathens'." (23.5)
Jubal sees the ability to identify or label other people as a way of gaining power over them, even if just in your own mind. Jubal uses this identity system to give Mike the upper hand at the world conference. Both the Fosterites and Mike use it to grant their disciples access to different levels of their churches.
"The sooner you act like an angel the quicker you'll feel angelic. Get Happy, junior!" (25.10).
Digby's identity conflicts with his actions. As an angel, he's supposed to be angelic, so when he isn't, it's a problem. The same could be said for other social identities in the novel, like when Cavendish and Anne take on the identities of Fair Witnesses.
"Ben, you noticed that Dawn and I have the same figure? Height, bust, waist, hips, weight, everything—not to mention coloration. We were almost alike when we met… then, with Mike's help, we matched exactly. Even our faces are more alike—but that comes from doing and thinking the same things." (31.188)
As Jill and Dawn ascend higher in Mike's church, they begin to lose their physical identities and start to look more and more like each other. It's kind of like when a dog and its owner start to look alike after a while... right?