This is the second part of a study on the handwritten corrections that I found in the original copy of the Kritik der praktischen Vernunft at the University of Erlangen-Nürnberg Library. Whereas the first part of that research resulted in a predominantly philological and historical investigation on those corrections taken as a whole, in this paper I focus on the philosophical meaning of a single correction, namely, the one on line 11 of page A166 of the original edition (Practical Reason, 5:93). There the word nur (only) was changed to nun (now), apparently with the intent of expressing more adequately the experiment with practical reason that Kant discusses in the passage.

With the help of Erlangen professors Jens Kulenkampf and Severin Koster (classical philologist), I obtained corroboration for a hypothetical dating of this particular change and others. Up until then the author of those corrections was unknown, and it was presumed that they had been made in the late eighteenth or early nineteenth century. The book, however, is signed by two previous owners, and the assumption was that their signatures were written down only much later, at the beginning of the twentieth century. Professor Koster was right about the first hypothesis, but not about the second. I found out that the signatures belonged to people who were Kant's contemporaries and belonged to his circle of relationships. I also found out that one of them, Paul Joachim Sigmund Vogel (1753–1834), was responsible for the corrections and had exchanged some correspondence with Kant.