World Logic Day was celebrated for the first time on January 14, 2019. The date chosen, 14 January, corresponds to the date of death of Kurt Gödel and the date of birth of Alfred Tarski, two of the most prominent logicians of the twentieth century. On 26 November 2019, UNESCO proclaimed 14 January to be World Logic Day and included it in its list of International Days. This year, World Logic Day will be celebrated for the fourth time. The event is very popular worldwide. Last year there were 82 scientific events in 40 countries and this year 50 countries have already registered to participate.