I take note of the fact that there are a lot of people who appreciate what I do as parliament president, not just within my Social Democratic party group, but also among the conservatives.

It is impossible to swear an oath to the German Basic Law without realizing that our constitution is among the most liberal constitutions in the world. As the head of government in such a country, I would stand up to all those who call into question this free, open and tolerant model of society.

When we were negotiating the ongoing financial period in 2013, I talked myself hoarse. London and Berlin in particular insisted on reducing the budget. So we - to the applause of German journalists - made cuts to central future-oriented areas and slashed the budget for development aid, research and technology.

Referendums are a democratic instrument, but so are decisions reached in a parliamentary democracy. I advise extreme caution when it comes to referendums. In Germany too.

If you say in advance there is going to be a main candidate and then that doesn't count later, then that's going to be a highly problematic occurrence in a democracy.

Donald Trump is withdrawing from the Paris climate agreement because he wants to lower environmental standards for American products and manufacture more cheaply. His reasoning is quite simple, but very shortsighted. It won't succeed because, by doing so, Trump is missing a golden opportunity to modernize American industry.

The old fundamental principles must continue to apply, even in our changing society: Democracy knows neither master nor slave. Equal education opportunities for all, no matter where they come from and no matter who their parents are. Equal access as well when it comes to digitalization.