Paul Gordan's theses were published in <A HREF="https://books.google.nl/books?id=9u09AAAAcAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false">De linea geodetica</A> and digitised by Google, from which I reproduce the relevant page: <IMG SRC="https://ilorentz.org/beenakker/MO/Gordan.jpg"/> Translation: - I. The method of <A HREF="https://en.wikipedia.org/wiki/Cournot_competition">functional division,</A> proposed by the respectable <A HREF="https://en.wikipedia.org/wiki/Antoine_Augustin_Cournot">Cournot</A> as an analytical and empirical method, appears unsuitable, since one does not have fully empirical functions. - II. The method of the infinitely-small is, I claim, no less precise than the method of limits. - III. It is of greater interest to investigate the implicit properties of a function defined by a differential equation than to investigate in terms of which known functions it can be expressed. - IV. The principles of Democritus remain to the present day as the foundation of the theory of atoms. One can also learn from this publication that the opponents of Gordan at the March 1, 1862 *Disputatio* were Dr. Kretschmer, Mr. Geiser, and Mr. Rathke, presumably <A HREF="https://www.genealogy.math.ndsu.nodak.edu/id.php?id=141906">E.E. Kretschmer</A> and <A HREF="https://www.genealogy.math.ndsu.nodak.edu/id.php?id=103791">C.F. Geiser</A>. Gordan acknowledges as his teachers in mathematics the professors <A HREF="https://en.wikipedia.org/wiki/Ernst_Kummer">Kummer,</A> <A HREF="https://en.wikipedia.org/wiki/Ferdinand_Joachimsthal">Joachimstal,</A> <a href="https://en.wikipedia.org/wiki/Friedrich_Julius_Richelot">Richelot,</a> <A HREF="https://en.wikipedia.org/wiki/Johann_Georg_Rosenhain">Rosenhain,</A> <A HREF="https://en.wikipedia.org/wiki/Heinrich_Schröter">Schroeter,</A> and <A HREF="https://en.wikipedia.org/wiki/Johann_Gottfried_Galle">Galle</A> --- but it is unclear whether any of these were present at the defence ceremony.