In our society there is more than exact opposition represented in the definitions of these two terms.
Polarization occurs often and without hesitation when talking in terms of black and white.
Mr. Head considers a black person in the same way he considers a dark night or a menacing image. Anything that steers away from the norm is considered dark or fearsome. Mr. Head feels that as Nelson grows up he is responsible for teaching him moral lessons concerning black and white. Nelson is oblivious to the racial prejudices that Mr. Head has concerning blacks. Nelson is uneducated in what a black person is supposed to look like.