Usual meaning: Post Scriptum, Latin: postscript. As still used today, to indicate postscript sentences in a letter.Beethoven used P.S. instead of a proper salutation: Pro Salute, Latin: to the welfare of.Editors of previous Beethoven letter editions thought that letters with the title of P.S. were letters written in reference to other letters, i.e. postscript letters. When taking a look at the content of the new comprehensive letter edition this assumption does not hold true any longer. Many of the letters titled P.S. are independent documents bearing address and seal. At the end of a letter Beethoven used P.S. like it is usually used, namely to indicate postscript information.