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Physics LibreTexts

1.22 Systems of Knowledge

What is so special about the scientific method? There is no doubt that this system of creating knowledge has transformed the human condition in only a few hundred years. If you doubt this, imagine living in a time before cars or telephones or antibiotics. All the innovations of technology start with pure scientific research. When Benjamin Franklin was asked what was the use of the electricity he had just learned to harness, he replied, "What use is a newborn baby?"

"Aristotle" by Francesco Hayez. Aristotle was a Greek philosopher and scientist. (384-322 BC). Click here for original source URL.

In everyday life we encounter other systems of knowledge besides the scientific method. One ancient system is called appeal to authority, which means citing the opinion of an authoritative person or book rather than using evidence and logic to prove a point. This system was especially prevalent in the Middle Ages, when scholars believed that ancient Greek, Egyptian, and Arab civilizations represented a golden age of knowledge and that there had been little progress since then. Therefore, instead of trusting their own observations and ideas, scholars cited old authorities such as Aristotle and Plato. To preserve ancient bodies of knowledge, medieval officials attacked anyone who contradicted the old authorities. Appeal to authority is very different from citing a reference when you write a paper on some topic. A citation should not be used to claim your argument is correct because some "Great Person" agrees with you, but rather to let your reader check the evidence from original sources.

Bronze statue of Giordano Bruno. He was put to death because of his ideas that did not go with the appeal to authority that was accepted at the time. . Click here for original source URL.

Appeal to authority is anti-scientific because it is not based on prediction, creative experimentation, and observation. Galileo, the first person to observe the universe with a telescope, remarked that the humble reasoning of one person is worth more than the opinion of a thousand authorities. Historically, the system of appeal to authority has led to terrible repercussions for those who challenged the traditional wisdom. In ancient times, Socrates was put to death for encouraging his students to question traditional ideas. In the Middle Ages, the philosopher and mystic Giordano Bruno was burned at the stake by the Roman Catholic Church for suggesting heretical ideas about the existence of other worlds and life-forms. Galileo was shown the instruments of torture by the Inquisition and sentenced to house arrest for presenting his evidence that planets move around the Sun. In each case, a pattern was repeated: authorities feared that the roots of their culture would be endangered if bold thinkers encouraged debate about new ideas.

One damaging aspect of the appeal to authority is secrecy. In the Middle Ages, secret societies passed on mystical symbols and supposed ancient knowledge only to people who were seen as being worthy to receive it — others could not examine the evidence. This is one reason that the scientific method was such a revolution. In the 1600s, the scientists who founded England's Royal Society debated whether to keep new discoveries quiet. They voted and decided to publish all scientific results. That debate started our modern tradition of open publication so scientists around the world can verify hypotheses by conducting their own experiments. The drive to share scientific data has spurred the most recent phase of the information revolution with the creation of the Internet and the World Wide Web.

Another belief system is superstition, which is based on irrational beliefs about the natural world. Most superstitions have their origin in ancient folklore. They have no basis in logical or rational thought. Rather they appeal to unseen and undetectable influences, which make them immune from scientific analysis. One of the most common types of superstition assumes that patterns in nature can predict or influence human destiny. For example, ancient Romans and other Mediterranean people often sacrificed animals, tore out their intestines, and "interpreted" patterns of the entrails as predicting the future. This practice is called divination. Reading patterns in tea leaves or patterns in the lines of your palm are similar ideas. The most widespread superstition of this type is astrology — the belief that the patterns of planets and stars in the sky when you were born somehow affect your personality and the events that will happen to you during the rest of your life.

Palmistry and astrology are certainly complicated belief systems, but that fact alone does not give them the power to explain and predict. Why do people believe in these ideas? Part of the reason is a phenomenon called "confirmation bias," which is well known to psychologists. When you read a horoscope in a newspaper or magazine, you are more likely to remember the parts of the description that fit you, rather than the larger number of parts that are vague or don’t fit at all. Similarly, you are more likely to remember the occasion when you broke a mirror and something bad happened than the other times when nothing bad happened. Many superstitions keep a surprising grip on our modern world. Try to notice how many apartment or office buildings have no 13th floor, or how many of your friends and acquaintances "knock on wood" for luck.

Still another system of determining truth dominates our modern legal and political system, and so influences much of our lives. This is the advocacy system, in which each participant or team advocates one position in an argument. You may have experienced this in a school debate class, where you were assigned to defend one position whether you personally supported it or not. It is the basis of our legal system. In court cases, the primary goal is not to present all the evidence, as in science, but to win the argument. The assumption is that the truth will emerge from this vigorous contest between the two sides. In practice, it can be a troubling system. For example, the side with the most money can frequently afford to develop the best case. In addition, evidence with a clear bearing on the case may be removed from consideration by the court for procedural reasons.

The advocacy system is also the basis of marketing and advertising. In an advertisement, you hear only one side of the case. You are unlikely to hear an ad whose goal is to evaluate fairly the pros and cons of each competing product! That is reserved for some consumer magazines, which use scientific tests and compare products. We should also notice that in the advocacy system the advocate can be as important as the argument. Think of the eloquent trial lawyer or the sports hero pitching a product. In a scientific debate there may be good speakers and bad speakers, and that can make a difference at a conference or indirectly, but the outcome is determined by the evidence.

There is an unfortunate idea gaining ground in our culture: the method of science is just one way among many for knowing the world. This is called "relativism," which holds that knowledge gained from science or a psychic or an astrologer or an old superstition is equally valid. We must acknowledge the limits of science. Not every phenomenon has a scientific explanation yet, and science alone is not sufficient to run human affairs — try for example to imagine systems of law or economics or medicine that had logic but no compassion. The scientific method is not perfect. Conservative scientists sometimes delay the acceptance of correct new hypotheses. Fraud exists, but it is rare because an important result will always be checked. Despite these flaws, knowledge in this century has progressed at a breathtaking rate. As a system for revealing the way nature works, science is without equal.