Task: Question Answering
Input (English): Passage: Currently, (2004), there are principles of canon law common to the churches within the Anglican Communion; their existence can be factually established; each province or church contributes through its own legal system to the principles of canon law common within the Communion; these principles have a strong persuasive authority and are fundamental to the self-understanding of each of the churches of the Communion; these principles have a living force, and contain in themselves the possibility of further development; and the existence of these principles both demonstrates unity and promotes unity within the Anglican Communion.  Question: What kind of force could the canonical principles be said to have within the Communion?
Output (English): living