ASTR 1210 (O'Connell) Supplement



We usually use the word "technology" to refer loosely to the raft of electronic devices and software services that seem to be everywhere in our lives today.

But "technology" has a much broader meaning. Anything that is useful to humans -- that has some practical application -- is an example of technology. That includes all electronics, of course, but it also includes almost every other material thing in our everyday lives, from T-shirts to refrigerators to skyscrapers; and it also refers to the enormous swath of practical knowledge and methodology that we make use of to survive -- as in agriculture and medicine.

Technology ranges from the highly sophisticated to the humble. PowerPoint slides are a familiar form of "teaching technology" --- but so is a piece of chalk. Important technologies in earlier times were very basic: the first human technologies to be developed were fire, stone cutting tools and weapons, and clothing from animal skins. Although other animals are capable of employing primitive tools, our human progenitors had surpassed them in sophistication as long as 3 million years ago. The fossil record shows that invention was slow at first, the important steps taking tens of thousands of years. That was because hunter-gatherer societies were very conservative and not welcoming of innovation because they lived on the edge of survival and could not take chances on diverting labor.

Almost by definition, civilizations are based on technology. The earliest civilizations in Mesopotamia and Egypt (ca. 4000-3000 BC) depended on the extensive development of technologies for building homes and governmental/religious structures; for agriculture, water supplies, transportation, ceramics, weaponry, methods of storing and conveying information, and so on. Domestication of horses, cattle, dogs, and other animals was another key technology. Many of the simple things we take for granted today -- like cotton thread, or glass windows, or aspirin -- are technologies that would have been highly prized by ancient societies.

Although they may not have been determinative, the available technologies were of great importance in shaping the behavior and values of early human societies -- the place and character of manual labor, for instance.

Egypt-Maya Pyramids

Left: The Giza Pyramids of Egypt (ca. 2500 BC); Right: Maya Kukulcan Pyramid (Chichen Itza, Mexico; ca. 900 AD).

Useful innovations spread quickly among societies that were in close contact with one another, but independent parallel development tended to occur in isolated societies. The ceremonial pyramids of Egypt and the Maya (see above) --- developed 8000 miles and over 3000 years apart, completely independently of each other --- are examples. The rates of development differed, and the sequences were never exact: for instance, the wheel was not important in North or South America before European contact in 1492. And although civilizations rise and fall, their basic technologies tend to survive. They are taken over by successor societies and propagate continuously into the future. As the writer L. Sprague de Camp put it:

"If there is any one progressive, consistent movement in human history, it is neither political, nor religious, nor aesthetic. Until recent centuries it was not even scientific. It is the growth of technology, under the guidance of the engineers."
Technology transcends culture and politics. The primary technologies employed by any society are an amalgamation of innovations from earlier times and cultures. We still use the arch -- invented by others but first used on a large scale by the Romans (after ca. 200 BC) -- as a basic element of architectural design. We still use Euclidean geometry (from ca. 300 BC) in uncountable daily applications.

But why did de Camp say "not even scientific" here? Don't we think of science as being essentially equivalent to technology and also as a continually "progressive movement"?

The technologies employed by civilizations before 1500 AD may have been sophisticated in many ways, but they were not grounded on a systematic, scientific understanding of nature. Today, 500 years after the beginning of the "scientific revolution," things are different. It is fair to say that we now live in a scientific civilization. This doesn't simply mean that many people are scientists or that most people have some education in science.

In this course supplement, we consider the effects of science and technology on society and how our scientific understanding of the operating principles of nature has affected human lives.

Relationship Between Science and Technology

Although science and technology are often intertwined they have different goals and value systems, and we need to clarify the distinctions between them:

Until the scientific era, new technologies were developed through trial and error, building on intuition drawn from everyday personal and societal experience. Beginning in the 17th century, science was a new analytical and contextual mode of thinking about the natural world. The main hallmarks of science were the rejection of supernatural explanations, a demand for repeated verification by empirical tests, and insistence on accepting new interpretations only if they were consistent with all the facts.

The influence of science on technology began slowly in the 17th and 18th centuries. But the pace accelerated as science demonstrated its value as a means to solve many problems that at first seemed intractable: e.g. questions like "what causes bubonic plague?" or "what are the stars?" By the mid-1800's, it was clear that science offered a demonstrably reliable and powerful understanding of the natural world.

Today, our scientific understanding of many aspects of the natural world is truly profound -- as it should be after hundreds of years of concentrated effort. It encompasses almost everything we encounter in everyday life. Consequently, science now usually precedes technology. Trial and error are certainly still central to technology development, but the essential foundations for experimentation come from science. Most of the important technologies of the last 200 years have been based on earlier scientific research.

The Critical Conceptual Path: All technology is utterly dependent on a huge store of knowledge and invention that extends far back in human history. For each important technology, we can construct a "critical conceptual path" of the main steps leading to its realization. Almost all modern technologies depend on a long list of discoveries in curiosity-driven basic science. Most will go all the way back to the 17th century scientists.

The "Big Four" Benefits of Technology to Modern Society

If you asked historians of technology to list the inventions or technological developments most important to today's society, you would get a range of opinion on the "top-ten." But any sensible list would include the following four categories:

Power Lines

Electricity: A Case Study

The most obvious manifestation of electricity today is in sophisticated electronics: smart phones, DVD players, HD TV, personal computers, video games, and so forth. But these are luxuries, and it should be easy to imagine being able to live comfortably without them---in fact, people did so only 30 years ago. We don't really need fancy consumer electronics, but we do need electricity. Our reliance on electricity is profound, and its use is so deeply embedded in the fabric of civilization that we mostly take it for granted. At least until there's a power failure.

If our knowledge of electricity could be somehow magically subtracted from the contents of a typical classroom, virtually everything would disappear --- except a bunch of naked people.

Development of Electric Technology

Electricity is the everyday manifestation of electromagnetic force between electrons and atomic nuclei, the second kind of inter-particle force (after gravity) that physicists were able to quantify. Here is a very brief history of our understanding of EM force, divided between "basic" and "applied" developments:

A Brave New World

The cumulative influence of science-based technologies, including the myriad applications of electricity and electromagnetic waves, has been profound. Living conditions for most human beings have been radically transformed for the better since 1500 AD.

By every measure -- lifespan, health, quality of life, liberty, equality, wealth, security, opportunity, and so on -- the present circumstances for the great majority of people are an unprecedented improvement over the past. They are an improvement even over the lifestyles of the most privileged individuals in earlier history --- there aren't many sensible people who would trade indoor plumbing for rubies and emeralds.

It's worth taking a moment to contemplate how different life was 500 years ago. You may not know who your ancestors were in the year 1500, but you do know two things about them: their lives were mostly not very good and not very long. The miseries of the 16th century were graphically depicted in this extraordinary 1542 painting by Pieter Bruegel. His visualization was, thankfully, exaggerated for effect. But look at the charts above as you ask yourself what your own life might have been like if you had been born in, say, 1900 -- a date only an instant ago in the context of all human history.

Technology alone is obviously not responsible for all the improvements of the last 500 years, but it is central to most of the changes in our material surroundings, and these are transpiring at an ever-increasing pace.

Examples like these demonstrate how important existing technologies are in shaping our behavior, our intuition, and our imagination -- in fact, our entire outlook on the world around us.

Technological Excesses and Boomerangs

Technology is never an unalloyed good. Given its rapid emergence, it is not surprising that modern technology has produced numerous unforeseen side effects and difficulties. All technology carries risk. Powerful technologies are obviously capable of both great benefits and great harm. The obvious historical example of a two-edged technology is fire. Novel technologies will frequently rechannel human behavior, with consequences that are hard to predict and can be deleterious. Technologies convey important advantages to groups or societies that possess them, and they can be used to oppress or exploit other groups.

As appreciative as we ought to be of the technologies that are the foundation of our material lives today, and as impressive as are new medical therapies or innovations in entertainment, there is a strong thread of discontent with technology that runs through our society. Some of this stems simply from frustration when technologies -- usually complex ones -- fail to work well or don't live up to inflated expectations.

But in the last 50 years, dangers attributed to science and technology have often been given more prominence than their benefits. People these days are often more suspicious than appreciative of science and technology.

The threats are consequences not of basic science but instead of the societal choices that are involved in developing any new technology -- which is always based on some perceived need or demand in society. The threats are also mostly inadvertent --- i.e. unforeseen by those who implemented the new technologies or grossly amplified by widespread adoption.

"Boomerangs," paradoxes, and ironies abound in the history of modern technology. Here are some telling ones:

In the early 21st century we are entering an era of technological transformation, similar to that produced by physics and chemistry in the 20th century, based on molecular biology, hyper-scale information processing, artificial intelligence, nanotechnology, and bio-electronics. Few, if any, scientists, government officials, or corporate leaders are perceptive enough to accurately forecast what this will bring only 25 years from now. As always, both benefits and risks have the potential to be enormous.


How should we respond to adverse technological "feedback"? A first impulse might be to argue that the associated technologies are so threatening that we ought to suppress them --- but this ignores the abundance of benefits they bestowed in the first place. The problem, a difficult one, is to achieve a healthy balance that preserves most of the advantages while mitigating the serious disadvantages of important technologies.

Technology could, in fact, solve many of the environmental problems we face --- assuming it is carefully designed and properly applied. Failures to adequately address such problems are rarely caused by serious technological barriers.

Instead, continuing threats from technology are usually the product of greed, incompetence, indifference, absence of foresight, or lack of political will. That certainly applies to the central environmental threat facing us and that we take up next.

The Biggest Threat

The root of almost all of our environmental problems is not any one technology. Instead it is the inevitable product of all of them, and it is something that almost everyone agrees is a good thing: modern technology keeps people alive. Life expectancy at birth has roughly doubled since 1850. Without a corresponding downward adjustment in birth rates, the increase in the human life span creates an imbalance between birth and death rates. The response to this imbalance is exponential population growth, where the increase in the population in any year is proportional to the population itself. The population will grow geometrically, not linearly, without limit, as long as the net birth rate does not go to zero. Of course, at some point exhaustion of resources will drastically increase the death rate, and the population will stabilize or decrease. That will stop the exponentiation, but we obviously would prefer not to rely on that solution.

Population growth is the ultimate source of almost all of the environmental threats we now face, including global warming.

Exponential growth is insidious. A tiny 2% excess of births over deaths in a given year implies a doubling time for the population of only 35 years. This is close to the actual growth for the human population between 1960 and 1999. At that rate, starting from 6 billion people in the year 2000, the total population would be 42 billion -- 7 times larger -- by the year 2100.

We may not yet have reached the "carrying capacity" of the Earth, but we are getting closer. We are probably already well in excess of the population that is compatible with easy resource sustainability.

Fortunately, as of 2019 the net birth rate has dropped to 1%, and the doubling time has increased to 70 years. Taking into account this important reduction, the population in the year 2100 is projected to be "only" 11 billion -- so the situation is less dire than it might have been. Nonetheless, demand from the growing human population has already crossed critical local resource thresholds in many areas, as attested by famines and other privations scattered around the world.

There is no doubt that unchecked population growth is the biggest technology-driven hazard facing the human race today. Population control is not a technologically difficult problem; effective innovations like the birth control pill are readily available. But there are serious ethical, not to mention political, quandaries in attempting to control or reduce the human population. Regardless, it is obvious that these must be intelligently confronted soon. Needless to say, prospects here are not good. You would be hard pressed to find American politicians for whom population control is a serious issue, let alone a high priority. In fact, policies on all sides of the political spectrum, including those embedded in the current federal tax code, are to encourage population growth.


Humans are technological creatures. The earliest urban civilizations depended on a plethora of important technologies. Useful innovations spread through contacts among societies and became widely adopted and built upon. Modern science emerged from astronomy and physics in the 16th and 17th centuries and invoked a new mode of thinking about nature by placing a premium on validating ideas by empirical tests. Its success in making sense of the natural and human worlds transformed the ways in which new technologies were developed and greatly accelerated the rate of their introduction. We now live in a scientific civilization: the main technologies we rely upon today were made possible only by a long "critical conceptual path" of basic scientific research which itself was mostly not motivated by practical applications. Realizing the benefits of modern technology while simultaneously minimizing their inevitable negative side effects is a difficult balancing act with which all societies struggle, sometimes without great success. The biggest technological threat facing the world is uncontrolled population growth, something that too few intellectual or government leaders are addressing seriously.

If there is one main lesson from the history of human technology it is that its trends and impact are difficult or impossible to predict. In terms of government policy, the best approach (apart from obvious crises) is good, broad support for basic scientific research and moderate (but alert and intelligent) regulation/stimulation of technology in the private sector.

And there is another fundamental obligation of a democratic society in the technological age: high quality public education. The danger of an uninformed electorate -- or, worse, government -- was nicely summarized by Carl Sagan in this 1995 quote:

"We've arranged a global civilization in which most crucial elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces."

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Last modified June 2022 by rwo

Text copyright © 1998-2022 Robert W. O'Connell. All rights reserved. These notes are intended for the private, noncommercial use of students enrolled in Astronomy 1210 at the University of Virginia.