Chapter 2 Questions


Question:

Why didn't the Arabs formulate new theories since they had a strong interest in astronomical science? Is it just western arrogance that their contributions are ignored?

Answer:

Islamic scholars studied and expanded upon the ideas of Ptolemy. They preserved and added to the existing cosmological studies for eventual transmission to Europe. Without this, how long would Europe have remained in the dark ages? Some Arab scholars were dissatisfied with Ptolemy, and some studied the ideas of Aristarchus. The Islamic scholars were instrumental in developing the abstract celestial deferents and epicycles of Ptolemy into real, physical celestial spheres. This was to be influential in the eventual overthrow of the Ptolemaic system by the observations of, among others, Tycho Brahe. Similarly their accurate monitoring of celestial positions provided the first indication of the small inaccuracies in the Ptolemaic tables. And finally, our modern star names (e.g. Rigel, Deneb) are names that have come down to us from Arab scholars.

Now, having said this, there is no doubt that the major shift in cosmological thinking occurred due to the work of a relatively few individuals in Europe during a relatively brief period of time in the Renaissance. Why was the Renaissance so special? Well, you could study this for a long time, but at least a few of the reasons were technological. The development of the printing press and the widespread availability of books was probably the greatest influence. Increase in trade, increase in personal wealth, etc. all were also important. The development and use of the telescope was obviously crucial to the development of new astronomical theories. Scholars have long debated the extent to which Copernicus was influenced by others (e.g. Aristarchus), but the world was ready for the heliocentric idea when he wrote it down. If Kepler or Galileo hadn't been born, no doubt others would have made their discoveries, but who and when?

There are and were a whole world of cosmological ideas. Here, we concentrate only on those that lead directly to the modern relativistic cosmology.

Question:

Europe made little progress in understanding the universe during the Middle Ages, in large part due to the Church doctrine which espoused Aristotelian astronomy. What was the official cosmological view of the Chinese and Arab civilizations during the same period, and did astronomers in those nations face the same opposition from the established church as European astronomers experienced?

Answer:

This is an interesting question which invites more extensive study. As another example of a conflict between "church" and "science," alchemists in the Near East, working to extend Greek theories of matter, were persecuted as magicians after the fall of Alexandria. One suspects any radically new ideas will always encounter some resistance from established governmental powers. Religion and government were often synonymous, and in some areas still are.

However, it is not inherent that there must be a conflict. For example, the more crippling aspect of Church doctrine in the Holy Roman Empire was that academic study of the material world was considered worthless; only the spiritual mattered. But, at the same time Islamic societies were encouraged by the Koran to study nature, hence much learning was preserved and extended. The Chinese took a practical interest in learning, although less, perhaps, for its own sake than for what you could do with it in the here and now.

Question:

How could someone explain the composition of humans and other organic objects using the simple Aristotlean table of elements?

Answer:

We might note that the body takes in air to exist, so must have a large component of air, clearly has fire (bodies are warm, and if ignited they will burn which is the release of elemental fire), contain water (you drink and excrete water), and earth (upon cremation, most of the nonearth elements are driven out). Much of the Aristotlean science was adopted and expanded into alchemical studies, including the idea of an "elixir of life." Since this isn't anything close to the correct description of how chemistry works, it is difficult to formulate a coherent theory of biochemistry out of the ideas of the ancient alchemists and philosophers.

Question:

What is an arcsec? How is it related to a parsec?

Answer:

An arcsec is a second of arc, 1/3600 of a degree. A parsec is the distance that a star would have if it shifted on the sky with a parallax angle of one second of arc.


Chapter 2 Return to Chapter 2   |   contents Table of Contents

Copyright © 1998 John F. Hawley