CHAPTER VII. 



KEPLER. 



" His celebrated laws were the outcome of a lifetime of speculation, 

 for the most part vain and groundless. . . . But Kepler's name was 

 destined to be immortal, on account of the patience with which he 

 submitted his hypotheses to comparison with observation, the candour 

 with which he acknowledged failure after failure, and the persever- 

 ance and ingenuity with which he renewed his attack upon the 

 riddles of nature." 



JEVONS. 



135. JOHN KEPLER, or Keppler,* was born in 1571, seven 

 years after Galilei, at Weil in Wiirtemberg ; his parents were 

 in reduced circumstances, though his father had some claims 

 to noble descent. Though Weil itself was predominantly 

 Koman Catholic, the Keplers were Protestants, a fact which 

 frequently stood in Kepler's way at various stages of his 

 career. But the father could have been by no means 

 zealous in his faith, for he enlisted in the army of the 

 notorious Duke of Alva when it was engaged in trying to 

 suppress the revolt of the Netherlands against Spanish 

 persecution. 



John Kepler's childhood was marked by more than the 

 usual number of illnesses, and his bodily weaknesses, 

 combined with n promise of great intellectual ability, seemed 

 to point to the Church as a suitable career for him. After 

 attending various elementary schools with great irregularity 

 due partly to ill-health, partly to the requirements of 



* The astronomer appears to have used both spellings of his name 

 almost indifferently. For example, the title-page of his most 

 important book, the Commentaries on the Motions of Mars ( 141), 

 t|as the form Kepler, while the dedication of the same book is signed 

 Ke| pier. 



179 



