In the year 1815 [1816], at his request I began teaching his nephew Karl, whom he had already adopted, and from that time I saw him almost daily, since for the greater part of the time he brought the little fellow to me. From this period I still have many letters written by him, one of which I reproduce here with absolute fidelity because it is musically noteworthy:
“I beg of you to have as much patience as possible with Karl even if matters do not go now as well as you and I might wish, otherwise he will accomplish even less, for (but this he must not know) he is already subjected to too great a strain because of the improper division of his studies. Unhappily this cannot be changed at once, therefore treat him with as much loving consideration as possible, but with seriousness; thus you will have better success with Karl in spite of the unfavorable conditions. In regard to his playing for you, I beg that not until he has acquired a correct fingering and can play in time and reads the notes with reasonable correctness, you direct his attention to the matter of interpretation, and thereafter not to stop him because of trifling mistakes but to point them out after he has finished the piece. Although I have given but few lessons I have always followed this method, it soon makes musicians which, at the last, is one of the first purposes of art, and gives the minimum of weariness to master and pupil. At certain passages like
I wish that you would use all the fingers occasionally as well in such as these
so that they may be played in a gliding manner. True, such passages sound ‘pearly’ as the phrase goes (played with few fingers) or ‘like a pearl,’ but at times other jewels are desirable. More at another time. I wish that you may receive all this in the loving spirit in which it is expressed and intended, at any rate I am and will always remain your debtor. May my sincerity be a pledge for future payment so far as possible.”
Noteworthy in this interesting letter is the very correct view that one ought not to weary the talent of a pupil by too much petty concern (wherein much depends on the qualities of the pupil, it is true) as well as the singular fingering and its influence on interpretation.
Much more valuable were Beethoven’s oral remarks about all kinds of musical topics, other composers, etc., touching whom he always spoke with the greatest positiveness, with striking, often caustic wit and always from the lofty point of view which his genius opened to him and from which he looked out upon his art. His judgment even concerning classic masters was severe, as a rule, and uttered as if he felt his equality. At one lesson which I gave his nephew he said to me: “You must not think that you will do me a favor by giving him pieces of mine to play. I am not so childish as to desire that. Give him what you think good for him.”
I mentioned Clementi. “Yes, yes,” said he; “Clementi is very good,” adding, laughingly “For the present give Karl the regular things so that after a while he may reach the irregular.”
After such conceits, which he was in the habit of weaving into nearly every speech, he used to burst into a peal of laughter. Since irregularities used to be charged against him by the critics in his earlier days he was wont often to allude to the fact with merry humor. At that time (about 1816) I began to have musical entertainments at my home for my very numerous pupils every Sunday before a very select circle. Beethoven was almost always present, he improvised many times with kindly readiness and with that wealth of ideas which always characterized his impromptu playing as much, or often more, than his written works. As his compositions were chiefly played at these meetings and he indicated the tempo, I believe that in this respect I am intimately acquainted with his wishes regarding his works (even his symphonies, which were frequently played in arrangements for two pianofortes).