Crüger to Müller, 1 July 1622
Peter Crüger, “Crüger to Müller, 1 July 1622,” Nova Kepleriana 4, July 1, 1622, 107–108, transcribed in Plain Old Text, https://sources.vjbe.net/stable/chzxw.
Nova Kepleriana 4 1 Jul, 1622, p. 107–108 Summary
Part of Die Keplerbriefe auf der Nationalbibliothek und auf der Sternwarte in Paris
Crüger finds Kepler's physical astronomy pleasing but obscure, accuses him of bending Tycho's observations to fit his harmonies and Copernicanism, and turns hopefully to Longomontanus's newly published *Astronomia Danica*.
Source: Peter Crüger's letter to Philipp Müller of 1 July 1622, written at Danzig, on Kepler's physical astronomy in the Epitome, which he finds pleasing but obscure, and on the Astronomia Danica of Longomontanus, just published on Tychonic principles, which he expects to trust more. The original is in the Bibliothèque de l'Observatoire, Paris (B, 1, 9; 89, 9. E. 27). Printed in extracts in Nova Kepleriana 4, ed. Walther von Dyck and Max Caspar, Abhandlungen der Bayerischen Akademie der Wissenschaften, Math.-naturw. Abteilung 31, no. 1 (Munich, 1927), 107–108.
Transcribed from: the page images of the 1927 printing.
Only the Latin is given; the editors’ German commentary and notes are left out. The 1927 edition prints only extracts. Each paragraph below is one of its extracts, and the omission marks (…) are the editors’. Spaced type, which the editors used for emphasis, is given in italics. Crüger’s own marginal note is given in parentheses after [margin:], where the editors put it. [Longomontani] is the editors’ gloss.
… Kepplerus dum Hypotheses Copernici rationibus Physicis demonstrare laborat, mirabiles introducit speculationes non tam ad Astronomiam quam ad Physicam pertinentes, quales sunt, de fibris Planetarum magneticis et aliae — ([margin:] „Ut motum Telluris annuum obtineat, totam fere philosophiam reformat et novam quandam introducit, novos etiam terminos Astronomicos fingit, exempli gratia Focos, fibras Solipetas et Solifugas etc.; taceo mirabilem prosthaphereseon calculum per areas triangulorum et sectorum circularium. Non itaque mirandum, si et novos modos proportionum novasque rationes introducat.”) Jucunda sunt illa quidem, sed admodum obscura, ut et illa de motu librationum caelestium ad librae rationes comparato …
Quis horum ad Astronomiam usus? Esto, pelliciat hisce speculationibus nonnullos ad Physicam suam caelestem et Astronomiam Copernicanam; at multos etiam ab ea deterrebit, praesertim cum viderint prodire alterius opera Astronomiam totam ad Hypotheses Tychonicas instauratam. Prodiit illa hoc anno, vigiliis et opera Christiani Severini [Longomontani], Tychonicarum observationum socio decennali, cuius viri honorifica fit mentio tum in Progymnasmatum Tychonicorum appendice, tum in praefatione libri de recentioribus mundi Phaenomenis.
Vidi inibi multam a Kepplero discrepantiam. Et quidni Severino potius astipuler quam Kepplero? cum Severinus unice insistat observationibus Tychonicis, Kepplerus ipsas observationes limitet ad libros suos Harmonicos et Astronomiam Copernicanam et Physicam suam caelestem, cum potius observationes deberent esse norma Astronomiae …
De magnitudinibus Planetarum Tychonicis a Kepplero dubitatis dico, quod ante dixi, me nec omnia assequi nec omnia recipere, quae Kepplerus in Physica sua caelesti inque Epitome Astronomiae Copernicanae tradit: siquidem observationes ipsas Tychonicas (quibus ipse nunquam interfuit, nec, si interfuisset, tot oculorum paribus par est) limitando, corrigendo et nescio quid invertendo, nil aliud agit, quam ut suam Mundi Harmoniam et Astronomiam Copernicanam omnibus numeris absolutam esse probet. Videbo, quid me docuerit Astronomia Danica Severini.