A tradition similar to Italy ("Wigilia", or 'Christmas Vigil') exists in Poland. The number of dishes is traditionally 12, but has been an odd number in the past. According to the "Słownik etymologiczny języka polskiego" ("Etymological Dictionary of the Polish Language") by Aleksander Brückner, the number of dishes was traditionally related to social class: the peasants' vigil consisted of 5 or 7 dishes, the gentry usually had 9, and the aristocracy, 11 dishes, but the even number 12 is also found today to remember the Twelve Apostles. It is obligatory to try a portion of all of them. Some traditions specify that the number of guests cannot be odd.