but in his relations with scientific men he was
affable and pleasant. He showed no jealousy of a rival, and was always
ready to recognise merit in others; nor did he hesitate to acknowledge
any error of his own when more recent discoveries proved that he was
wrong.

Some of his works contain passages, written in a jocular strain,
indicative of a bright and cheerful temperament. The following
characteristic paragraph refers to the opinions of the Epicureans with
regard to the appearance of a new star, which they ascribed to a
fortuitous concourse of atoms: 'When I was a youth, with plenty of idle
time on my hands, I was much taken with the vanity, of which some grown
men are not ashamed, of making anagrams by transposing the letters of my
name written in Latin so as to make another sentence. Out of Ioannes
Keplerus came _Serpens in akuleo_ (a serpent in his sting); but not
being satisfied with the meaning of these words, and being unable to
make another, I trusted the thing to chance, and, taking out of a pack
of playing-cards as many as there were letters in the name, I wrote one
upon each, and then began to shuffle them, and at each shuffle to read
them in the order they came, to see if any meaning came of it. Now, may
all the Epicurean gods and goddesses confound this same chance, which,
although I have spent a good deal of time over it, never showed me
anything like sense, even from a distance. So I gave up my cards to the
Epicurean eternity, to be carried away into infinity; and it is said
they are still flying about there, in the utmost confusion, among the
atoms, and have never yet come to any meaning. I will tell those
disputants, my opponents, not my own opinion, but my wife's. Yesterday,
when weary with writing, and my mind quite dusty with considering these
atoms, I was called to supper, and a salad I had asked for was set
before me. "It seems, then," said I aloud, "that if pewter dishes,
leaves of lettuce, grains of salt, drops of water, vinegar and oil, and
slices of egg, had been flying about in the air from all eternity, it
might at last happen by chance that there would come a salad." "Yes,"
says my wife, "but not so nice and well dressed as this of mine is."'

Notwithstanding the frequent interruptions which, owing to various
reasons, retarded his labours, Kepler was able to bring to a successful
completion the numerous and important works upon which he was engaged
during his lifetime, the voluminous n