When I found topics dear to me, treated in a documentary I felt a warm pleasure. The theoretical and abstract notion of stocks and flows that I caress multiple times per day, in my mind, in my work, in my life, seen represented with actual tanks and water flowing was a nice surprise. That’s a machine, an analog computer, showing how money flows from the state to all of its stakeholders and it shows it with water. What a wonderful way of using a labyrinth of tanks and pipes with water flowing thanks to gravity. The author is searching for the origin of knowledge and she asked the water-based system dynamics machine if education and knowledge were connected to economics: of course!, he replied, they are directly connected. And he shows what happens when the state does not finance public education anymore and the student debts become a bank loan so the national debt gets hidden! And that was explained in a few seconds, some lever adjusted and water flowing. That documentary will be a source of many more connections.