Answer:
He didn't know he was "contaminated" before the letter.
Explanation:
The above question is related to the story "Desiree's Baby".
It is important to note that the word "contaminated" is used in this story in a racist way, as it refers to black people.
Armand belongs to a noble family and has fair skin, in addition to features that keep him from the characteristics that black people have. In addition, he is a handsome, wealthy man, with influence in the city and good contacts. He believes that black people and their descendants are "contaminated", however, he does not know that his mother was black, which makes him, despite having lighter skin than his slaves, is a descendant of black and, according to his concepts , contaminated.
He only learns of this after reading a letter written by his father.