Q: Why are there so many abbreviated names in Dostoevsky's works? In almost every book I read by Dostoevsky, I encounter a name or a place named S. OR T. or something along those lines. In the Idiot, Aglaya's sister's fiance was named Prince S.A: This is common in 19th century literature. You can see the same thing in Edgar Allan Poe, and probably a lot more. It certainly seems to us stilted, contrived and artificial.
It is a kind of disclaimer, in fashion at the time, and like the old police detective TV programs "the names have been changed to protect the innocent," quickly fell out of favor.
Prince S. I have assumed was never named, because a writer like Dostoevsky didn't want to take on the headache, lawsuit, or general hassle, of naming a member of the nobility in the Idiot, even by accident.
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(answer courtesy of Pavo:
http://www.fyodordostoevsky.com/yabbse/index.php?board=6;action=display;threadid=246)