George fears that they will lose their jobs if they are not careful in their conversations. Because most of the men searching for jobs traveled alone and were isolated from anyone with whom they worked, they are distrustful of two men traveling together. These men might wish to infringe upon the plans of Lennie and George. Or, sometimes they are even suspicious of the relationship between two men:
Curley lashed his body around. ''... he's gotta talk when he's spoke to. What the hell are gettin' into it for?' 'We travel together,' said George coldly. 'Oh, so it's that way.'
George is also concerned that if someone antagonizes Lennie, Lennie may seriously injure or kill the person. Since they were sent away from the last place where they were employed, George stresses to Lennie to keep quiet. Unfortunately, his fears are founded and Lennie tragically gets into very serious trouble as he accidentally kills Curley's wife.
When George, Lennie, and Candy realize they have a workable plan to buy a small ranch that George knows of, George warns the other two not to discuss their intentions:
Don't tell nobody about it. Jus' us three an' nobody else. They li'ble to can us so we can't make no stake. Jus' go on like we was gonna buck barley the rest of our lives, then all of a sudden some day we'll go get our pay an' scram outta here.
Once the dream seems truly within reach, George begins to imagine and worry about anything that might disrupt their plans.