How the ideas of a secret order influence Beethoven

In Slate magazine, Jan Swafford wrote an intriguing article about he influence of Christian Neefe on the young Beethoven. Neefe belonged to a secret order called the Illuminati, which sought to spread ideas of the Enlightenment by indocrinating youth. He probably did influence Beethoven a little bit. It's too bad that the article doesn't contain any direct quotes from Beethoven to support its thesis. That would've strengthened the argument.