I want to know the answer to the following question:
On what day was Ali appointed as the prophet's successor?
All the background I'm provided with is that "Shias believe that Imamah is of the Principles of Faith (Usul al-Din).As the verse 4:165 of quran expresses the necessity to the appointment of the prophets; so after the demise of the prophet who will play the role of the prophet; till the people have not any plea against Allah.". Is that enough to answer the question?
Answer: no