He has been called the "German Locke,"[4][5] on the basis of a comparison of his major work Philosophische Versuche über die menschliche Natur und ihre Entwickelung (1777) with the work of John Locke. He is considered to have been an influence on Immanuel Kant.
In 1776, Tetens became Professor of Philosophy at the University of Kiel. Nonetheless, in the years following 1789, Tetens began another career as a high-ranking Danish civil servant: member of the Finanzcollegium in Copenhagen, then (1791) counselor of state, and (1803) co-director of the state bank and director of the widow pension funds. By this time, he was interested in pure mathematics as well as in applications. His interest in polynomial algebra was influenced by his belonging to the German combinatorial school of Carl Friederich Hindenburg, Christian Kramp and others. His main applied work was concentrated on actuarial mathematics. He taught at Kiel until 1785.
The book Einleitung zur Berechnung der Leibrenten und Anwartschaften, published in Leipzig in 1785 (first part) and 1786 (second part) was a landmark of actuarial science. It contains an extensive synthesis of previous work on the subject, from Halley's mortality table to Richard Price's Observations on reversionary payments. It is recognized by actuaries for featuring the first risk measure ever (the Risico der Casse);[6] moreover it offers some insights in mathematical statistics: by using an approximation of the binomial distribution, Tetens tried to compute the confidence level of a given sampling procedure.[7]
Works
Gedanken von einigen Ursachen, warum in der Metaphysik nur wenige ausgemachte Wahrheiten sind (1760)
Abhandlungen von den Beweisen des Daseins Gottes (1761)
Ueber den Ursprung der Sprache und der Schrift (1772)
Ueber die allgemeine speculativische Philosophie (1775)
Philosophische Versuche über die menschliche Natur und ihre Entwickelung, Vol. 1 and Vol. 2 (1777)
Einleitung zur Berechnung der Leibrenten und Anwartschaften die vom Leben oder Tode einer oder mehrerer Personen abhangen mit Tabellen zum praktischen Gebrauch, Vol. 1 (1785) and Vol. 2 (1786)
Reisen in die Marschländer der Nordsee (1788)
Sprachphilosophische Versuche (posthum, 1971)
References
^Herman Jan de Vleeschauwer [de], The development of Kantian thought: the history of a doctrine, T. Nelson, 1962, p. 86.
^Tetens, Johannes Nicolas, Philosophische Versuche über die menschliche Natur und ihre Entwickelung. 2 Vols. Leipzig, 1777.
^Jan Rohls, Protestantische Theologie der Neuzeit, Volume 1, Mohr Siebeck, 1997, p. 201.
^Manfred Kuehn, "Hume and Tetens," Hume Studies, XV.2 (November 1989), 365–376, esp. p. 368.
^Cf. the appellation that was given to Kant: the "German Hume" (Manfred Kuehn, Kant: A Biography, Cambridge UP, 2001, p. 256).
^Text of the “Versuch über das Risico der Casse bey Versorgungsanstalten”, in Risques, n° 81-82, pp. 114-120
^Pierre-Charles Pradier, "L'actuariat au siècle des Lumières: risque et décisions économiques et statistiques", Revue économique 54 (2003): 139–156.