Final answer:
The mother's act of only calling David 'the Boy' is intended to dehumanize him, deny him his identity, and assert control by stripping him of his sense of self-worth.
Step-by-step explanation:
The effect that the mother hopes to have on David by only calling him “the Boy” in 'A Child Called It' is likely one of dehumanization and detachment. By refusing to use David's name, the mother strips away his individuality and the personal connection usually forged through the use of one's given name.
This act of calling him merely 'the Boy' can be seen as an attempt to reduce his sense of self-worth and identity, thus making him feel insignificant and unworthy of love and human dignity.
In literature, names are often symbolic and carry significant weight in defining a character's identity. For example, in William Wordsworth's writing, he claims that “the child is father of the man,” suggesting the importance of childhood experiences in shaping one's adult identity.
By denying David his name, the mother denies him the affirmation of his existence and worth that a name commonly confers. It is a form of psychological manipulation and control.