Jacek Jan Kuroń (Polish pronunciation: [ˈjat͡sɛk ˈjan ˈkurɔɲ]; 3 March 1934 – 17 June 2004) was one of the democratic leaders of opposition in the People's Republic of Poland.

Kuroń was a prominent Polish social and political figure known for his efforts at reforming societies under the control of the Soviet Union.

[1] As an educator and historian, he first postulated the concept of a de-centered movement that would question the totalitarian system and its personality cult.

Kuroń started out as an activist of the Polish Scouting Association trying to educate young people that would take charge of the future; he later co-founded with Antoni Macierewicz the Workers' Defence Committee or KOR, a major dissident organization that was superseded by Solidarity in August 1980.

After the changes in independent Poland, he ran for president supported by the likes of Jan Karski and served twice as Minister of Labour and Social Policy.

Kuroń was born in 1934, in Lwów (now Lviv, Ukraine), into a family that supported the Polish Socialist Party (PPS).

From 1952, he worked as a full-time employee in the capital scout section affiliated with the Association of the Polish Youth.

After the political transformation and introduction of democracy to Poland, Kuroń became a Minister of Labor and Social Policy.

A heavy drinker and smoker, he suffered from numerous health issues, including a stroke in 1998, throat cancer, atrial fibrillation and kidney failure.

Although Kuroń was an atheist, representatives of all major religious communities came to display their respect to the renowned humanitarian.

He suggested replacing the existing system with workers' democracy, including organizing a referendum according to which major decisions concerning a distribution of national income would be made.

The Coastal Free Trade Union WZZ, the cradle of Solidarity, was established on April 29, 1978 after Krzysztof Wyszkowski convinced Kuroń that workers needed their own voice.

His last public speech in April 2004 was addressed to alterglobalists, who were protesting against the World Economic Forum held in Warsaw.

The riddle of the yellow thermos was uncovered in the book Urban Legends by Mark Barber and Wojciech Orliński.