The other day Angela Merkel took a few hours out from the cacophony of day-to-day politics. Putting to one side migration, the eurozone, Russia and Ukraine, Brexit and the rest, the chancellor gave a speech about algorithms. Yes, algorithms.

Her message to an audience in Munich was that the search engines that deliver news on websites such as Google and Facebook are creating distorting prisms. The closely guarded formulas, or algorithms, used by these companies to tailor the output to recorded personal preferences can create echo chambers. Citizens eventually may receive only the news that fits their prejudices — a gift to today’s populist proponents of post-truth politics. Healthy democracies depend on the wide exposure of conflicting ideas and interpretations.

At the very least, Ms Merkel said, it was incumbent on the technology companies to be transparent about the way the algorithms are constructed, so viewers and readers understood they are being offered a strictly limited perspective on the world around them.