Introduction
摘要
The purpose of this Introduction is to provide a general idea of the history of thought regarding comets, situating the phenomena of 1618 in the context of mainly European history, explaining the comet-related observational issues in the early days of telescopic astronomy, as well as discussing cometary symbolism and (quasi)theology. A digression was prompted by the fact that, according to Kepler, the first of the three comets of 1618 was discovered in Cassovia (the author’s hometown). Last but not least, there is a brief overview of the chapters constituting this volume.