Because Lennie is stupid and has the common sense and knowledge of a five year old.
George knows that Lennie's cognitive impairment would prevent him from being able to care for himself successfully. Without George's guidance and protection, Lennie would likely struggle to meet his basic needs and may unknowingly put himself in dangerous situations. George believes it is best for Lennie's safety and well-being to stay together.
Lennie says he will go live in a cave if George gets fed up with him and does not want him around anymore.
george made Lennie feel strong he needed george to live and Lennie took evey word george said and though he forgot he would always turn to george and ask for him to help as there is a bit in the book that says george told Lennie to jump of a bridge into water and Lennie did even thought he could not swim and then thanked george for saving him.
George wishes he could live a simpler life without worrying about taking care of Lennie. He wishes he could travel and find work without the burden of looking out for Lennie's safety and wellbeing.
George initially wants to have a peaceful life and own a piece of land with Lennie where they can live independently and tend to rabbits. He shares this dream with Lennie to give him hope and something to look forward to.
In John Steinbeck's novel "Of Mice and Men," Lennie and George share a dream of owning a piece of land where they can live self-sufficiently and free from the difficulties of working for others. They envision themselves living off the land, with Lennie tending the rabbits and George overseeing their home. This dream represents their desire for independence, stability, and a sense of belonging.
George feels that because he and Lennie are family he has to protect him. Also he feel sympathy for Lennie whopossesses the mind of a child. One of the book's themes seems to be loneliness so you could argue that Lennie was also George's companion and they live of each other's strength. (I would give a quote but i can't find my book. The answer is somewhere in chapter 1).
they both work in a ranch that Curlys dad owns.
George says he will buy Lennie a piece of land with a little house and some animals, so they can live off the fat of the land and not have to work for anyone else.
When George gets angry with Lennie for causing trouble, he threatens to go to a place where Lennie won't be able to find him and live an easier life without the burden of taking care of him.
Lennie is lonely in "Of Mice and Men" because he struggles to connect with others due to his mental limitations. His reliance on George as his only friend and caretaker highlights his isolation and vulnerability in a world that often misunderstands or mistreats him. His desire for companionship and understanding is evident in his interactions with animals and in his repeated longing to live on a farm with George.
dont know