, , , , ,

It’s the first Friday of the month, which means it’s time for another guest post about the history of the theory of atoms from physics professor and my dad, Dean Zollman. Here, we find ancient knowledge preserved in the medieval Islamic world.—Kim

By Dean Zollman

Dean ZollmanMany years ago, before the way to find information was typing on a computer, I needed to verify some historical information for a textbook that my wife, Jackie Spears, and I were writing. As I was browsing in a library, I came across Alan Franklin’s small book, The Principle of Inertia in the Middle Ages. As a physicist with some knowledge of the history of my subject, the words “inertia” and “Middle Ages” seemed incongruous.

I knew that Aristotle got it wrong. He thought that an object’s natural state was sitting at rest. Thus, it took a force to keep an object moving, even at a constant speed in a straight line. My view was that Aristotle’s physics held sway until Galileo and Newton explained that an object keeps moving at a constant speed in a straight line or stays at rest unless an external force acts on it. The object’s inertia is this tendency to keep doing what it has been doing unless something forces it to change.

Intrigued, I read Franklin’s book and learned that science did not stop with Aristotle and restart after the Middle Ages; instead a flourishing scientific endeavor was taking place in the Middle East and Northern Africa while Europe was suffering through the so-called Dark Ages.

Scholarship was a major undertaking in the Middle East during approximately the eighth to 16th centuries. Some people call the science from this time Islamic Science because it is closely connected to the areas of the world that practiced Islam. Others argue that it should not be associated with a religion and prefer Arabic Science because the language of scholarship was Arabic even though many of the scholars were not Arabs. Independent of the name, scientific strides were accomplished in many areas including astronomy, medicine, mechanics, optics, and chemistry.


The Kitab al-Bulhan is a composite astrology/astronomy/geomancy Arabic manuscript from the late 14th century (public domain image via Wikimedia Commons).

In addition, in the eighth century, paper manufacturing was brought from China—to the Middle East but not Europe. Books became relatively inexpensive, and over about two centuries, a major translation effort was completed. Much of the classic works from Greece, Rome, India, and Persia were translated into Arabic and distributed throughout the lands that were under control of the Arabic Empire.

As you know from reading The Cross and the Dragon, at that time this territory included parts of Spain. So when Charlemagne took his army to Spain to help a Muslim ally overthrow the emir of Córdoba and prevent an invasion of Francia, he would have been just a little early to have seen some of these books or met some of the Arabic scholars. Of course, Charlemagne had other things on his mind than intellectual discussions with Saracens.

Atoms did not play a major role in Arabic science. However, Islamic philosophers had some of the same problems as early Christians. How does one reconcile atoms that are eternal with God creating the universe? The Kalam, an Islamic school of philosophical theology, was able to deal with this and other issues by developing a set of twelve propositions for the atom. I won’t try to describe all of them here.

One proposition states that time comes in instances which are separated from each other. Another involves properties, called accidents, of substances. These accidents include properties such as color, smell, motion, or rest, but also life and death.

The most important proposition is that accidents do not cross instances in time. Instead it is the role of God to create the accidents at each instant. For something to continue to exist as it did in the previous instant, God must re-create the accidents. Otherwise, the substance would cease to exist. Thus, creation seems to be happening continuously.

As I understand this (and I don’t pretend to understand it well), a pile of snow is white because God has created the accident whiteness in each atom of the snow. God must at each instant in time re-create this whiteness for the snow to remain white. Thus, this arrangement solves the problem of creation and eternal atoms because God is always acting to maintain the properties of atoms.

As I said at the beginning, this (or any) view of atoms was not a central part of Arabic science. Many of the strides made in scientific disciplines during the Middle Ages later became part of Western science. The “portal” through which many of them passed was the Islamic culture in Spain. As the Dark Ages subsided, many of the classic Greek, Roman, and Indian works that were then available in Arabic because of the eighth through 10th century translations were translated once again. This time the translation was from Arabic into Latin. Thus, the scholarship in the Middle East may have saved some classic works from being lost.

At the same time during the late Middle Ages some people were rediscovering some of the classics, such as Roman poet Lucretius’ The Nature of Things, which describes the basic ideas of the Greek atoms. This rediscovery is a story that I will save for next time.


What Are Things Made of? Depends on When You Ask.

Ancient Greeks Were the First to Hypothesize Atoms

The Poetry of Atoms

Atom Theory in Ancient India

Religion, Science Clashed over Atoms

Dean Zollman is university distinguished professor of physics at Kansas State University where he has been a faculty member for more than 40 years. During his career he has received three major awards—the National Science Foundation Director’s Award for Distinguished Teacher Scholars (2004), the Carnegie Foundation for the Advancement of Teaching Doctoral University Professor of the Year (1996), and American Association of Physics Teachers’ Robert A. Millikan Medal (1995). His present research concentrates on the teaching and learning of physics and on science teacher preparation.