Answer:
Racial Discrimination and the need to fight against it is a major theme in the story, and Mr. Lindner serves as a symbol of that matter.
Mr. Lindner´s attempt to bribe the Youngers to keep them from moving into the all-white Clybourne Park neighborhood is led by his and the Improvement Association´s discriminatory ideas against black people. And how that attempted bribe almost tears the family apart makes the reader aware of the prevailing discrimination, even when the violence that it generates seems a negotiation more than an act of oppression.
The importance of following one´s dreams is another important theme in this play, and Walter is a great symbol of this idea: he wants to accept the bribe so they can have money and buy nice things for the family. But by the end of the story, when he refuses the money and acknowledges that the dream of having their own house is the most important dream for the family. His character, and this development, also symbolizes the theme of the importance of family, and his change throughout the play helps the reader better understand how difficult his situation was and how much he needed to be more aware of his family´s feelings.
Step-by-step explanation:
In "A Raisin in the Sun," by Lorraine Hansberry, the importance of dreams, family, and fighting against racial discrimination are the main themes.