nevertheless there soon came to be much more liberty of speculation in Protestant than in Catholic
countries, because in Protestant countries the clergy had less power. The important aspect of
Protestantism was schism, not heresy, for schism led to national Churches, and national Churches
were not strong enough to control the lay government. This was wholly a gain, for the Churches,
everywhere, opposed as long as they could practically every innovation that made for an increase
of happiness or knowledge here on earth.
Copernicus was not in a position to give any conclusive evidence in favour of his hypothesis, and
for a long time astronomers rejected it. The next astronomer of importance was Tycho Brahe
( 1546-1601), who adopted an intermediate position: he held that the sun and moon go round the
earth, but the planets go round the sun. As regards theory he was not very original. He gave,
however, two good reasons against Aristotle's view that everything above the moon is unchanging.
One of these was the appearance of a new star in 1572, which was found to have no daily parallax,
and must therefore be more distant than the moon. The other reason was derived from observation
of comets, which were also found to be distant. The reader will remember Aristotle's doctrine that
change and decay are confined to the sublunary sphere; this, like everything else that Aristotle said
on scientific subjects, proved an obstacle to progress.
The importance of Tycho Brahe was not as a theorist, but as an observer, first under the patronage
of the king of Denmark, then under the Emperor Rudolf II. He made a star catalogue, and noted
the positions of the planets throughout many years. Towards the end of his life Kepler, then a
young man, became his assistant. To Kepler his observations were invaluable.
Kepler ( 1571-1630) is one of the most notable examples of what can be achieved by patience
without much in the way of genius. He was the first important astronomer after Copernicus to
adopt the heliocentric theory, but Tycho Brahe's data showed that it could not be quite right in the
form given to it by Copernicus. He was influenced by Pythagoreanism, and more or less fancifully
inclined to sun-worship, though a good Protestant. These motives no doubt gave him a bias in
favour of the heliocentric hypothesis. His Pythagoreanism also inclined him to follow Plato
Timaeus in supposing that cosmic significance must attach to the five regular solids. He used