Johann Friedrich Mieg

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Johann Friedrich
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Johann Friedrich Mieg (or Miegius, 1642–91) studied in Heidelberg, Groningen (1658) and Leiden. He was professor of theology at Heidelberg University (from 1665 onwards). Mieg held his inaugural lecture in theology on 15 June 1691 at Groningen University in 1691 and died one month later. See: Drüll, 1991, pp. 103–6.

Although a fair number of scholars in the Leipzig academe at least for a period seemed to have stayed uncertain about the identity of the author of Tractatus theologico-politicus, Spinoza’s name was already familiar to well-informed intellectuals at Heidelberg University. That becomes evident from a relatively unknown letter, dated 28 June/8 July 1670 dispatched from Heidelberg by the theology professor and Hebraist Johann Friedrich Mieg Sr to his friend and Herborn colleague Samuel Andreae. In his letter, Mieg tells his correspondent that it had come to his notice that a work on ‘the liberty to philosophise’ only just recently came out in the United Provinces. Mieg also gives away to Andreae that the same book was authored by an apostate Jew called Spinoza. According to the Heidelberg theologian, he had also edited a geometrical digest of Descartes’s 1644 Principia philosophiae:

I hear that in the Netherlands appeared a treatise on the liberty to philosophise, written by Spinoza, a former Jew (whose Cartesian Philosophy set forth according to the geometrical method I have), arousing commotion there, and departing very far from the truth and from the religion we owe to Scripture. But so far I did not have the opportunity to see it.

Source: The Hague, Museum Meermanno, ms. MMW 7 A 8, no. 112 (Mieg to Andreae, 332 letters).

The source of Mieg’s information is completely unknown, but since he is reported as having studied in the Netherlands in 1663 he perhaps got the information revealing the identity of the author of the ‘Theological-Political Treatise’ from one of his Dutch contacts or from Dutch students enrolling in Heidelberg.


Samuel Andreae