Page 435 - 89 history of astronomy_opt

Throughout this evolution of thought and
conjecture there were two types of astronomers–
those who supplied the facts, and those who
supplied the interpretation through the logic
of mathematics. So Ptolemy was dependent
upon Hipparchus, Kepler on Tycho Brahe,
and Newton in much of his work upon Flam-
steed.
When Galileo directed his telescope to
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