Why does Antonio’s mother have so much hope that Antonio will be a “man of learning”? What is her “definition” of this term?

In the fall, Antonio starts going to school for the first time. He is extremely nervous on his first day, but his parents argue with each other instead of quelling his fears. Antonio’s father reiterates that Antonio has Marez blood, while Antonio’s mother continues to declare fiercely that he will follow his Luna ancestry. She reminds her husband that, when Antonio was a baby and Ultima offered him all of the objects of life, he reached for the pen and paper. Before Antonio leaves, his mother asks Ultima to tell her what Antonio will be when he grows up. Ultima replies sadly that Antonio will be a man of learning. Triumphantly, Antonio’s mother quickly pushes him out the door and on his way to school. As Antonio leaves his house, he feels as if he is seeing Ultima and his parents the way they are for the last time. Learning would entail both religious and secular knowledge.

She wants him to become a "priest." This is what she means by a "man of learning."