We get a lot of information right up front about the characters, but they don't really come to life until we see them in action. Shmoopsters, trust what the narrator tells you, but then watch it play out. You'll be glad you did.
About Archie, the narrator says: "This was the man: never able to make a decision, never able to state a position" (3.50). Then we see Archie's indecision manifest over and over again throughout the novel—like when he flips a coin to make major life decisions. Because that totally gets him off the hook.
We learn directly that Joyce Chalfen needs to be needed, and then we see her coddle Millat. Millat, we are told, is a tough kid who runs with a bad crowd. And then we see him harassing ticket sellers at train stations.
This narrator tells you what to expect from these characters up front, and then demonstrates their main qualities for you. Well, most of the time anyway.
Kind of like in life, characters in White Teeth are constantly commenting on the physical appearances of other characters. For example, we've got Marcus saying to Irie "You are a big girl […] We like that around here—a healthy eater" (12.18-20). And Joyce thinking about Millat's beauty:
Beauty in a tall brown young man who should have been indistinguishable to Joyce from those she regularly bought milk and bread from, gave her accounts to for inspection, or passed her checkbook to from behind the thick glass of a bank till. (12.15)
Over and over again, characters and the narrator comment on Millat's Roman nose, Irie's hair, Samad's attractiveness for an older man, and Alsana's weight. These characters are all trying to work out who they are and where they belong, their physical appearances are tied up in those journeys.
Right from the beginning, with Archie's attempted suicide (quite a place to begin now that we think about it), the characters in White Teeth are defined by their positions in society. Archie goes to die in Cricklewood, which he thinks is "no kind of place," but that's just the kind of place where he feels it would be right for him to die:
The way Archie saw it, country people should die in the country and city people should die in the city. Only proper. In death as he was in life and all that. It made sense that Archibald should die on this nasty urban street where he had ended up, living alone at the age of forth-seven, in a one-bedroom flat above a deserted chip shop. (1.2)
We can see here how Archie thinks of himself.
When the Chalfens enter the novel, they bring with them a whole different social world than any of the Iqbals or Joneses are used to. The Chalfens are Cambridge-educated, liberal intellectuals. From the first time Irie goes to their house, she knows they are different than she is. And she likes what they have:
She'd never been so close to this strange and beautiful thing, the middle class, and experienced the kind of embarrassment that is actually intrigue, fascination. (12.67)
By dropping Irie Jones and Millat Iqbal into this middle-class home, the novel highlights how very different these families' lives have been. But if you think about the FutureMouse event at the end of White Teeth, social status can't account for or predict everything. All the kids in this novel torture their parents; a comfortable middle-class home doesn't stop Joshua Chalfen from acting something like Millat Iqbal.
When people talk about White Teeth, they often talk about the way that characters speak. Zadie Smith presents us with a wide range of dialects and different kinds of location-based speech, where characters change their talk based on their circumstances. Language is pretty darn powerful in this novel.
When Millat and his crew are trying to buy train tickets to go to a book burning, they are struggling with their identities. Millat uses a very specific kind of speech in this moment:
I just say, yeah? One for Bradford, yeah? You got some problem, yeah? Speaka da English? This is King's Cross, yeah? One for Bradford, innit? (9.161)
And his friends chime in behind him with a chorus of "yeah." Millat uses this kind of speech to sound tough, and also to indicate that he belongs to a particular group called Raggastani.
Clara, too, uses different ways of speaking at different times to affect others' perceptions of her. When Alsana tells Clara she's pregnant, Clara is so surprised, she doesn't remember to control her language:
Clara blushed the moment after she had spoken; she always dropped into the vernacular when she was excited or pleased about something. (3.143)
When Clara has strong emotions, she slips into what might be more natural for her—her Jamaican accent. But she usually tries to sound more English.
So, the way characters speak in White Teeth tells us a lot about how society sees them. And how they see themselves.