1651-1708

German mathematician, physicist, and philosopher who traveled extensively between the various intellectual centers in his time, and became a veritable clearinghouse of new ideas in science and technology. In his book Medicina Mentis ("Mental Medicine," 1687), Tschirnhaus laid out a method of discovering rational truths as a basis of a happy life derived from Cartesianism, Spinoza, the English empiricists, and Leibniz, whom he greatly admired. Only true knowledge can tame the emotions, he believed, which are the sources of error and therefore of unhappiness. Later in life he rediscovered how to make hard-paste porcelain.