This article is Copyright © 2009 Published by Elsevier Inc.
To the Editor:
Inspired by the article by Drozdov et al. Evolution of one-handed piano compositions, [1, Copyright 2008 American Society for Surgery of the Hand] we would like to add 2 annotations on the issue of hand loss and its potential influence on 20th-century politics and philosophy.
One-handed pianist Count Géza Zichy happened to bear a striking physiognomic resemblance to the German emperor, Wilhelm II (1859 1941), whose left arm was severely shortened and paralyzed, presumably owing to birth-related brachial plexus palsy or intrauterine hypoxia. Wilhelm blamed his British doctor for this deformity: An English doctor crippled my arm. It has been theorized that this feeling of inferiority due to his functional one-handedness may have produced an overcompensation that led to Wilhelms narcistic, aggressive, and belligerent personality and, ultimately, to World War I.[2,3]
As a second note, we think it is important to know that, although Paul Wittgenstein lost his right arm physically during World War I, he preserved its cortical representation, as observed by one of his piano pupils: He told me I should trust his choice of fingering because he felt every finger of his right hand. At times I had to sit very quietly while he would close his eyes and his stump would move constantly in an agitated manner. This was many years after he had lost his arm. His finger choice was always the best.
Paul lost 3 brothers by suicide; his youngest, Ludwig (18891951), became one of the most influential philosophical thinkers of the 20th century. His last book, Ueber Gewißheit (On Certainty), concerns the nature and limitation of knowledge and language, and it explains that certain things must be exempt from doubt to make human practices possible. He starts this text by 2 sentences on the fundamental certainty as the certainty of our bodies: 1. If you do know that here is one hand, well grant you all the rest. 2. From its seeming to meor to everyoneto be so, it doesnt follow that it is so. Although this last manuscript was a response to analytic philosopher G. E. Moore, it seems likely that Ludwig was inspired by the example of his brothers phantom handamputated, yet real, certain, and functional. 
Recently, bionic prostheses, especially using targeted muscle reinnervation, have been able to provide
the sensory feedback (eg, of shoulder skin) to amputees who feel like it is in their missing arms and
Phantom sensations and motions can be translated into real movements, probably in the future
enabling even one-handed pianists to play bimanually again. Indeed, it is interesting to imagine the reaction of both Paul and Ludwig Wittgenstein to these new devices.
Andreas Gohritz, MD
Karsten Knobloch, MD, PhD
Peter M. Vogt, MD, PhD
Plastic, Hand and Reconstructive Surgery
Medizinische Hochschule Hannover