Steinbeck gives the impression in Chapter 4 that Crooks reads to fight off his loneliness. In the description of Crooks's room in the barn, Steinbeck writes that
"he had books, too; a tattered dictionary and a mauled copy of the California civil code for 1905. There were battered magazines and a few dirty books on a special shelf over his bunk" (67).
The condition of the books and magazines--"tattered," "mauled," and "battered" implies that Crooks has mulled over the reading material many times and even has a special place for these possessions when many of his other things are "scattered about the floor." Also, as Crooks talks to Lennie, he says,
" 'A guy sets alone out here at night, maybe readin' books or thinkin' or stuff like that' " (73).
The reader knows that the reading and "thinkin'" don't satisfy Crooks, but he has no other recourse. He's not allowed to eat or sleep in the same quarters as the other men, and it seems that only time he gets to communicate with them is when they want to make a bet over him or use him for entertainment.
Of all the characters in the book, Crooks's isolation is the most striking and intense. Unlike Curley's wife, he has no spouse who even cares where he is or whom he talks to. Unlike George, he has no one depending on him or listening to him. Unlike Candy, he has no canine companion. He cannot even find comfort or companionship with the animals that he tends to, because one of them caused his painful, lasting injury.