This plaque is laid in the ground at Bebelplatz in Berlin, the historic site of the Nazi book burning. Nearby is a small glass-covered chamber that descends into the ground, like an up-right coffin. All that is inside are empty bookshelves.
On the plaque is a quote from 1820 by the German Jewish poet, Heinrich Heine. It reads, "That was only a preview, where man burns books, in the end he also burns men." (my translation)
Something to keep in mind, in these days filled with anger.