During his travels he met Baruch de Spinoza and Christiaan Huygens in the Netherlands, Isaac Newton in England, and Gottfried Wilhelm Leibniz (with whom he maintained a lifelong correspondence) in Paris.

His work Medicina mentis sive artis inveniendi praecepta generali (1687) combines methods of deduction with empiricism and shows him to be philosophically connected to the Enlightenment.

[6] After he returned home to Saxony, von Tschirnhaus initiated systematic experiments, using mixtures of various silicates and earths at different temperatures to develop porcelain, which at the time was available only as a costly import from China and Japan.

The use of kaolin (from Schneeberg, Saxony) and alabaster advanced the work, so that August II named him the director of the porcelain factory he intended to establish.

The Elector ordered payment of 2,561 thalers to von Tschirnhaus, but the recipient requested postponement until the factory was producing.

Three days after Von Tschirnhaus's death, there was a burglary at his house and, according to a report by Böttger, a small piece of porcelain was stolen.

Work resumed on 20 March 1709, by which time Melchior Steinbrück had arrived to assess the dead man's estate, which included the notes about making porcelain, and had met with Böttger.

In 1719, for example, Samuel Stölzel of the porcelain factory of Meissen went to Vienna with the still-secret recipe and confirmed that it had been invented by Von Tschirnhaus and not by Böttger.