Promoted to the doctorate in 1505, he lectured on philosophy at Montaigu College and on theology at Navarre.
Thence with much spirit, and in face of many difficulties, he betook himself, with his colleague Edward Frankland, to the university of Marburg (1848-1851), where, by intense application, he obtained his doctorate in two years.
At first he followed a legal career at Pavia and Bologna, and when in 1499 he took his doctorate he was esteemed the most learned canonist in Europe.
In 1818 he received the doctorate of theology and of canonical law.
His French thesis for the doctorate of letters, Etude sur les pamphlets politiques et religieux de Milton (1848), showed that he was attracted towards foreign history, a study for which he soon qualified himself by mastering the Germanic and Scandinavian languages.
After taking his doctorate in law in 1846 he joined the Parisian bar.
The student desiring to proceed to the doctorate is free from examinations thereafter until he presents his thesis for the doctor's degree,' when, if it is accepted, he is submitted to a public oral examination not only in his principal subject (Haupt f ach), but also as a rule in two or more collateral subjects (Nebenfeicher).
He also prepared two theses for his doctorate in philosophy, De primis socialismi germanici lineamentis apud Lutherum, Kant, Fichte et Hegel (1891), and De la realite du monde sensible.
In the faculty of sciences a candidate for the doctorate may submit two theses, or else submit one thesis and undergo an oral examination.
For the doctorate in the faculty of letters two theses must be submitted, of which the subject and plan must be approved by the faculty (until recently one of them was required to be written in Latin).