Alice Calaprice in The Guardian:
Although Albert Einstein was a prolific writer, he did not think of himself as one. “In the past, it never occurred to me that every casual remark of mine would be snatched up and recorded. Otherwise I would have crept further into my shell,” he wrote in a fit of frustration to his biographer, Carl Seelig, in 1953. By this time, two years before his death, his archive contained more than 20,000 items, thousands of which were written by him personally. Today, the archive has more than doubled in size.
A physicist, philosopher, humanitarian, pacifist, political agitator and cultural Zionist, Einstein was also a formidable writer, and very quotable. Because he wrote almost exclusively in German, his words have been translated into dozens of languages – though, as everyone knows, much can be lost in translation.
Translators have difficulty reproducing his sentences faithfully because they inevitably need to move the words around, causing them to lose their rhythm. Moreover, some of Einstein’s words have been so miserably mistranslated that one can’t recognise the original. Different versions can also lead to confusion about what he actually said. Einstein, as is the case with most writers, is best read in his mother tongue.