Post-truth is an adjective that relating to or denoting circumstances in which objective facts are less influential in shaping public opinion than appeals to emotion and personal belief. 1
Some sources says that President Ronald Reagan brought down the Berlin Wall because in 1987 Reagan made a speech where he said: “Gorbachev, tear down this wall!”.
This is a post-truth because the Berlin Wall was overthrown by KPD, the Communist Party of Germany, and not by President Ronald Reagan.
I can prove that the fall of the Berlin Wall is a post-truth because I found the following information:
President Ronald Reagan brought down the wall.
Many Americans believe that Ronald Reagan’s June 1987 speech in Berlin — “Mr. Gorbachev, tear down this wall!” — led to the wall’s fall in 1989. However, Mikhail Gorbachev’s reforms in the Soviet bloc were far more important than Reagan’s speech, as were the actions of the East Germans themselves.
When the wall started to fall on Nov. 9, it was a mistake. In the face of mass protests against the regime in 1989 and thousands of East Germans seeking refuge at West German embassies in Eastern Europe, East German leaders waived the old visa rules stating that citizens needed a pressing reason for travel, such as a funeral or wedding of a family member. East Germans would still have to apply for visas to leave the country, but they would supposedly be granted quickly and without any requirements.
Yet the Communist Party official who announced these changes, Guenter Schabowski, missed most of the key meeting about the travel procedures and went unprepared to a news conference on Nov. 9. In response to reporters’ questions about when the new law would take effect, he said, “ Immediately, without delay .” Schabowski left the impression that people could immediately cross the border, though he meant to say they could apply for visas in an orderly manner.
Over the next several hours, thousands of East Berliners gathered at the checkpoints along the wall. Since the country’s leaders hadn’t intended to completely open the border, the supervisors at the crossing points had received no new orders. The chief officer on duty at the Bornholmer Street checkpoint, Harald Jaeger , kept calling his superiors for guidance on how to handle the growing mass of increasingly angry East Berliners expecting to be let through. Jaeger finally gave up around 11:30 pm and allowed people to pass through en masse. Guards at other crossing points soon followed suit. The East German regime never fully regained control.
Anonymous, Dictionary, [website], 2015, https://en.oxforddictionaries.com/definition/post-truth, (accessed 2 December).