Did beethoven use the “Enneadecaphonic” theory?

Abstract The 19‐tone equal temperament suggested since 1500 by great theoreticians, never accepted by classic composers (and now easily implemented, as well as systems of frequencies without musical value, by synthesizers), is shown to be the only system which would allow to formulate basic musical features (not explicitly appreciated centuries ago) in a non‐ambiguous algorithmic theory useful to composers.