Describe the events which occured on the "day of unamity".

The Day of Unanimity is like the ancient Christians' Easter. As a boy, D-503 prepares an hour calendar to count down the wait. New unifs are distributed. Every year, Numbers wear them to witness the annual reelection of the Well-Doer. It is symbolic of their powerful union, quite unlike the unpredictable elections of the ancients, conducted in darkness and secrecy. Moderns all vote openly for the Well-Doer. Unseen Guardians care for anyone who might do otherwise.