  In that year, Leibniz met Baron Johann Christian von Boineburg, a Protestant convert to Catholicism, who was able to secure a position for Leibniz with the Elector of Mainz. While in the court of the Elector, Leibniz composed a series of works in philosophical theology, the Catholic Demonstrations, which are another manifestation of Leibniz's lifelong irenicism: in this case, in their attempt to provide a basis and justification for the reconciliation of Protestantism and Catholicism. Leibniz also turned his mind to natural philosophy, having finally been able to study some of the works of the moderns; the result was a two-part treatise in 1671, the New Physical Hypothesis (Hypothesis physica nova). The first part, the Theory of Abstract Motion (Theoria motus abstracti), was dedicated to the Académie des Sciences de Paris, and the second part, the Theory of Concrete Motion (Theoria motus concreti), was dedicated to the Royal Society in London. These works, however, were not likely to impress their audiences, for, given his circumstances, Leibniz could not but produce amateurish works in the field.