Because he believes words cannot be trusted, Heller relies mainly on action to develop his characters. In most cases, the characters say one thing and often do another. For the most part, actions often show just how low a character really is. There are some, however, that show some virtuous qualities. The chaplain, for instance, tries to talk to Colonel Cathcart and Major Major about reducing the number of missions. And during Thanksgiving, Nately runs after an enraged Yossarian to try to stop him from killing the prankster shooters.
Heller offers many physical descriptions of his characters. Sometimes they reveal something about a character's character. Milo, for example, has "disunited eyes" which "could see more things than most people, but…could see none of them too distinctly." This shows Milo's blindness, his inability to see how his dedication to the syndicate could be interpreted as a betrayal of his country or how he could attack his own base but have a problem bribing the government.