In Of Mice and Men, the conflict begins when George and Lennie are running away from the last ranch in which they worked. Lennie has a desire to touch soft things. He doesn't know his own strength. He he so strong, and he can harm a pet or even a human being before he realizes what he has done.
When Lennie becomes afraid, he has a tendency to panic. Lennie is mentally handicapped. He is childlike. He will burst out sobbing if his feelings get hurt:
Lennie is mentally handicapped: he cannot quite remember what had happened in Weed; he speaks with a child's vocabulary; and he bursts into tears when George makes him give up the dead mouse that he has been secretly petting in his pocket.
Lennie creates conflict without trying. He keeps George upset at him. Lennie breaks Curley's hand and George has to break up the fight. Next, Lennie kills the puppy. Ultimately, Lennie breaks Curley's wife's neck. He never meant to harm anyone. Lennie was trying to quiet Curley's wife.
Because George cannot handle or realizes Lennie cannot handle what Curley will do to him, George shoots Lennie in the back of the head, thus ending the conflict for Lennie.
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