How could the Tur disagree with his father if a son may not contradict his father?

A source-based Torah discussion of the question: How could the Tur disagree with his father if a son may not contradict his father? This localized discovery layer presents the canonical issue for search and study without adding a new practical ruling. The author-fidelity publication clearance is preserved, while the full Hebrew source remains the controlling text for its reasoning, qualifications and conclusion.