The paper discusses Timothy Snyder’s On Tyranny. Twenty Lessons from the Twentieth Century. It has become a best-seller, translated into many languages, it had to be reprinted in Poland and the USA. Why is such a small book so sough-after? The author analyses Snyder’s motivations for writing the book; then goes on to show that being an academic does not mean ridding oneself of the professional academic/humanist’s workshop when one decides to speak publicly in an urgent case. Snyder’s book, using the lessons of the 20th century history and the advice provided by the 20th century thinkers, intellectuals, researchers from the Central and Eastern Europe, is a collection of instructions for everyone on how to be a responsible citizen, regardless of their political views.