Euler's Letters to a German Princess: Translation and Betrayal – Conclusion

At the end of this, my exploration of Euler’s Lettres, what have we found?

Certainly, I am pleased that, 250 years after they were written, the letters remain rich in scientific, philosophical, and didactic content. Readers looking for assistance with the technical details can consult scholarly assessments such as the older article and more recent book from Ron Calinger (the latter written with Katya Denisova and Elena Polyakhova) [Calinger 1976; Calinger 2019]. However, when attempting to consult the primary source, we seem to find ourselves in an uncomfortable position: this brilliant work, one of Euler’s most popular books, exists in English only in bowdlerized form. Perhaps even more alarmingly, we discovered that going back to the French original is helpful only if we use the very first printing—too many changes have snuck in (and back out again) during later printings.

Fortunately, in our modern information age, the original is readily available online [Euler 1768–1772]; moreover, the Opera Omnia has reprinted and re-typeset the original faithfully. To anyone interested in reading or using the Letters to a German Princess, I cannot recommend too strongly the importance of checking assertions and quotations against these renderings of the original French text. It’s now clear to me how very vital it is to have a new translation of the Lettres—one written in modern English, and one faithful to Euler’s work. Until this work is finished, Euler’s legacy to the English-speaking world will not be complete.