In chapter 2 of the novella, George and Lennie introduce themselves to the boss of the ranch, who expresses his authority by asking probing questions, warning both men, and giving them direct orders. Before meeting the boss, George instructs Lennie to remain quiet and let him answer all the questions. George understands that Lennie's mental disability is obvious whenever he speaks and does not want the boss to fire them the moment hears Lennie talk.
Unfortunately, Lennie cannot help himself and repeats George's comment when he praises him for being "strong as a bull." Once Lennie speaks, the boss recognizes that something is not quite right and demonstrates his authority by challenging both men. The boss does not want to take any chances on hiring deceptive connivers and instantly stands up to George.
The boss suspects that George is taking advantage of Lennie and proceeds to question his intentions. George quickly defends himself by claiming that Lennie is his cousin, and the boss contemplates the situation. The boss then tells George and Lennie,
But don’t try to put nothing over, ‘cause you can’t get away with nothing. I seen wise guys before. Go on out with the grain teams after dinner. They’re pickin’ up barley at the threshing machine. Go out with Slim’s team.
The boss shows his authority by issuing a warning to George and Lennie. They understand he has the power to let them go, and his warning makes it clear that he is willing to fire them at any moment. His next comment reveals his experience, which shows the men that he is shrewd and clever enough to recognize a scam when he sees one. The last lines of the quote are specific directives. As boss of the ranch, he has the power to give orders and instructs George and Lennie to go "out with the grain teams after dinner."