This past September, I had the pleasure of meeting Ryan Estrada at SPX. During one of our conversations, he let drop an interesting bit of trivia about himself: he has only said the "F" word once. At the time, I didn't press him on why he leaves that particular word out of use, or about what motivated him to make that single exception, but those questions stayed with me. Given that this is an increasingly common and, many would argue, particularly useful word, the conscious decision not to use it necessarily raises interesting questions about Ryan as a person: Does he take a moralistic view of obscene language? Or does he take the view that cursing is a crutch for those with small vocabularies? Or is this just another of the odd personal challenges he tends to assign himself?
All of which is to say that the small details of the words people use and how they choose to express themselves reveal quite a lot about who they are and what they value. While there's certainly more to writing comics than just the text, there's no denying that the writer's most visible contribution to comics is in the words themselves, especially dialogue. It's easy to make the mistake of writing characters who speak the same way you do — it's certainly what's going to come most naturally. And it can work for certain types of comics: journal comics, political comics, or other comics that are designed to give the author a direct mouthpiece. But it doesn't do much for developing a story with a cast of multiple distinct characters.
Different people speak differently; they use different words and different syntax. Understanding the individual speech mannerisms of your characters will go a long way toward helping you distinguish them from each other, as well as from yourself. Does a particular character speak in short clipped sentences? Long, rambling monologues? Are they plainspoken, or do they like to use colorful metaphors? Do they use a lot of complex technical jargon?
And perhaps most importantly: Why? Speech mannerisms shouldn't be arbitrary, unless you're just playing it for laughs — they should be expressions of the character, revealing more about who they are and how they think than the content of their speech alone would do. For that same reason, when answering the question of why characters speak the way they do, it's important to go beyond simple stereotype. It's easy to decide that a character uses lots of technical jargon "because she's a scientist." But "scientist" isn't a character; it's a background detail. There's no reason why a scientist must necessarily use constant technical jargon at all. Some scientists also like to read poetry. Or go to church. Or drink beer while watching football. And all of these things will affect the way they speak just as much as their technical background. Possibly even more so in casual conversation. Sure, the technical jargon is likely to fly freely in the lab, but in a restaurant, or a bar, or at a friend's party, other impulses take over. Our careers do influence how we communicate, but that's just one of a multitude of factors.
An excellent example of clearly distinguished, expressive dialogue can be found in Spike's Templar, Arizona. Right from the opening sequence, we see sharp contrasts in speech mannerisms. Mr. Pierce, the cantankerous newspaper editor, speaks in long rambling sentences, punctuated with violent imagery. He employs genuinely sophisticated vocabulary and tough-talking vulgarity in equal measure, and uses both to assert his superiority over Benjamin, the story's protagonist. (Admittedly, the angry newspaper editor is a stereotype, but Pierce appears to be a minor character, so it's not as big of an issue.) Benjamin, by contrast, is quiet and non-confrontational. He uses only the most perfectly neutral language, saying as little as possible, frequently not even going so far as to articulate actual words.
Taking the idea of expressive dialogue a step further, not only do people take their speech cues from myriad sources, but they also tend to modify their manner of speaking in different contexts. Most people don't talk the same way at work as they do at home. They don't talk the same way with their parents as they do with their friends. We use different words, different syntax, different modes of communication as befits the context and the audience of what we're saying.
This is perhaps nowhere clearer than in the case of vulgarity, an entire classification of words that are considered acceptable in some contexts but not others — though those contexts can vary from person to person. Most people will refrain in a religious institution, out of politeness, if not faith. On the other hand, some people are perfectly at ease swearing in front of their parents, while others would never think of it. And, of course, there are some people who consciously choose not to use these words at all. Or who only curse when they're very upset. Or only during sex. Or who curse vocally, but never in writing (or vise versa). Some people will curse freely among members of their own sex, but rein it in among members of the opposite sex. Some people use expletives in a calculated way, placing them for greatest effect. Others pepper every statement with expletives, like they're just another kind of comma.
The important thing to remember is that the particular usage should demonstrate not the author's attitude toward coarse language, but each particular character's attitude toward it. Too often, writers treat expletives as a binary, with either no expletives at all, or constant expletives, completely neglecting the fact that everyone has their own personal style of swearing. Knowing when a character is and isn't willing to use coarse language can reveal a great deal about their comfort level in different situations and around different people. It can reveal the settings they consider sacrosanct, or the people to whom they are deferential or respectful. Even minor fluctuations in a character's use of expletives can reveal insecurity, or pride, or reverence.
Looking again at Templar, Arizona, there's Benjamin's neighbor, Reagan, a powerful presence who takes over any conversation with casual confidence. Like Pierce, she provides a clear contrast to Benjamin's reticence, but without the hostility. She curses just as freely, but where Pierce used vulgarity as a weapon, Reagan's cursing is casual and unaffected — it belies an honesty that puts you at ease about her intentions, even when she's making you do things you don't want to do (such as forcing Benjamin to go out and see the city, despite his hermitic tendencies).
And against the backdrop of both Pierce and Reagan, foul-mouthed pair that they are, Benjamin's own failure to utter even a single curse word thus far is glaring. It comes off not as a moral choice, or a matter of respect, but simply another symptom of his insecurity around people. He doesn't curse because words like "fuck" are stronger than he is. He's just not ready to handle that kind of language — not in the face of other people, anyway.