Possible Clues:

• Determining factor
• Motive for an action
• Logician's need
• Seditious crime, losing head and sound judgement
• Stands to this about a boy
• That's why it's about a boy of yours
• Cause; think logically
• Is this why it's about a boy of yours?
• Why this is about one's boy
• Is that why it's about a boy of yours?