What are "mommy's contradictions"?

From the text:

"Mommy's contradictions crashed and slammed against one another like bumper cars at Coney Island. White folks, she felt, were implicitly evil toward blacks, yet she forced us to go to white schools to get the best education. Blacks could be trusted more, but anything involving blacks was probably substandard... She was against welfare and never applied for it despite our need, but championed those who availed themselves of it."