Walter has this brillant idea to invest in a liquor store with two of his buddies, BoBo and Willie. His part of the investment would be $10,000, which happens to be the amount of the insurance money Mama has inherited from Big Walter. Walter Lee has it in his head that if he invests in this liquor store,it will rise him and his family out of the "slums". It would make him feel proud to be a man. When his wife, Ruth ignores his idea and does not listen to him, his self-esteem lowers and he gets angry because he wants so badly to be the man of the house, proud and well-respected.
Beneatha is also very adament about not getting married. She feels school and learning her heritage to Africa is the most important thing in her life. The amount she likes man is determined on the amount he gives her. This is shown in her discussion with mother when she speaks of only going out with George Murchinson because he takes her to nice places. Also this is illustrated when she was never interested in Asagai before, but then he mentions taking her to Africa with him and she contemplates marrying him.
The first way in this clip Beneatha insults her mother indirectly is when she sounds out Asagai's name unneccessarily slow: AS.AG.GAI. .
The next way Beneatha's pride gets in the way of respecting her mother's intelligence is when she asks her mom not to "ask any ignorant questions about Africa.". This insults Mama while making Beneatha look well-educated and pompous.
Mama has a deep ingrained pride in her. Most of her pride is from the inherited pride she received from her late husband, Big Walter. She has the good old values of putting your family first, respecting your mother and father, and respecting the Lord. .
She always talked about how her generation won their freedom and was proud to be able to no longer be thought of as slaves. She never seemed to fully understand the type of pride Walter Lee was searching for although she tried.