Things that aren't science
Before we address this, good to note what it isn't, because popular culture tends to confuse the issue significantly.
- Science isn't the same as technology.
Technology is the useful application of knowledge (obtained my any method) to solving practical problems. Science is a specific method by which we can get knowledge to begin with, but it is not the only one. In the modern era, however, new technologies are often applications of scientific discoveries. E.G. tunnel capacitors, practical electronic components based on the application of the rather academic field of principles of quantum mechanics.
Nevertheless, many complex technologies have been around much longer than the practice of science and were developed by simple trial and error.
- Science isn't a body of knowledge.
This message often gets garbled in public education, where "learning science" typically means "learning the information that the practice of science has yielded" rather than about the practice itself. Contrary to what "creation scientists" would have you think, you aren't doing science simply by referring to the scientific body of information while wearing a lab coat. You actually need to be using a very specific method.
- Science isn't purely descriptive.
There are many ways to describe nature. Whether the descriptions are "scientific" or not depends on whether they contain repeatable observations that can be used by the scientific method or not.
Fundamentally, science is methodological.
Why do we need a Scientific Method?
Because the human mind doesn't automatically process information in a way that's conducive to scientific thinking.
Consider Thomas Kida's Six-Pack of Problems.
- We prefer stories to statistics. No surprise. The human mind, as we know it today, seems to have arisen around 30,000 to 40,000 years ago and contains characteristics inherited from even earlier ancestors, but we have had access to the kind of compiled information that forms the basis of statistics (right) for only the last 5,000 years.
- We seek to confirm, not to question, our ideas. No surprise. All humans are, to some degree, egotists. Many of us are pathologically incapable of admitting a mistake. Training ourselves constantly to question our own ideas, especially the ones we really want to believe, requires genuine discipline.
- We rarely appreciate the role of chance and coincidence in shaping events. The idea that "shit happens" is a surprisingly modern one. We cling desperately to the notion that if we do the right things we will be OK and abhor the idea that random events (the drunk running into our car, the lightning bolt, etc.) can effect us. History, literature, and folklore are full of examples of human attempts to find order in chaos. Consider:
- The Iliad - The chaos of a prolonged and disorganized war transformed into poetry by the superimposition of a coherent story of a conflict among the gods.
- 2 Samuel 6:7-8 (right)
- The Right Stuff by Tom Wolfe (1979)
- We sometimes misperceive the world around us. No surprise. We don't uniformly pay attention to everything in our environment. We focus on certain things and ignore others. Indeed, we routinely indulge in observational selection, where we preferentially notice facts that confirm our beliefs. In some cases, we may actually hallucinate.
- We tend to oversimplify our thinking. No surprise. Life doesn't often give us time to perform thorough analyses of all options. Our ability intuitively to pick out a manageable number of good choices is usually a survival skill. (As the cartoon indicates, failure to do so seems strange.) When a leopard is bearing down on you, you don't have time to evaluate every possible escape route.
- We have faulty memories. We are suggestionable. Our memories can easily be influenced by our desires and expectations.
To protect us from these natural tendencies, we have developed a range of critical thinking skills. Think of them as the mental equivalent to martial arts skills. They don't come naturally but are very powerful, and have to be learned. They include:
The hypothetico-deductive method of science
History
Scholars used "science" and "knowledge" interchangeably since the Middle Ages. Starting in the early 19th, the word "scientist" (coined by the polymath William Whewell in 1833) began to replace "natural philosopher," and the word "science" was applied in a stricter manner than previously. Their methods evolved by trial and error. Generally speaking, by the middle of the 19th century, they were testing hypotheses in an essentially modern way, but didn't have a technical vocabulary to describe what they did.
That vocabulary was supplied by the 20th century philosopher Karl Popper (1902 - 1994). His motivations:
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Einstein's falsification of Newtonian mechanics, which seemed unassailable for 200 years.
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Proliferation of powerful intellectual movements that claimed to be doing science, or to employ it even though they refused to acknowledge the clear refutation of their predictions, especially:
- Marxism
- Fascist "scientific racism"
- Freudian Psychoanalysis.
Popper observed the behavor of real scientists to determine what they really did. Popper noted that how the method was applied varied a great deal depending on the circumstance. E.G.:
- A chemist or physicist might be able to set up many repetitions of carefully controlled experiments in a laboratory, whereas...
- A geologist or astronomer would have to employ observations taken from the rough and tumble of nature.
Nevertheless, certain common threads characterized all science:
- Repeatable observations
- Hypothesis falsification
- formulation of Theory
So let's look closer. More
Dissecting the Scientific Method
The guiding principle of scientific inquiry was perhaps best summed up by a non-scientist, the novelist Arthur Conan Doyle, who placed into the mouth of his character Sherlock Holmes these words:
The modern practice of science is based on a method that employs that principle, with a little twist.
Observations:
- Observations / data: Any impression of the physical universe that comes to us directly through our senses or indirectly through instruments. E.g. "I looked out my east window this morning and saw the Sun rise."
- Repeatability: The ability of two different individuals operating under the same circumstances independently to make the same observation. E.g. "My neighbor down the block also saw the Sun rise in the east."
Some types of observations are inherently non-repeatable. E.g. "My wife is the most beautiful woman in the world." Sweet, but unlikely that all observers would have the same impression.
- Patterns: Tend to become apparant when we make and compare many observations. E.g. "The Sun appears to rise in the East every morning." Humans are compulsive pattern recognizers, both seeing real ones and confabulating ones that aren't really there. The scientist's task is to distinguish the two.
- Hypothesis: A formal statement about a pattern of observations whose truth or falsehood is initially unknown. E.g. "The Sun always rises in the East." Remember, a hypothesis is a statement about a pattern of events, not a single observation.
- Hypothesis falsification: the scientific method does not absolutely prove anything. It can, however, disprove things. We do this by looking for observations that are inconsistent with our hypothesis. When a such an observation is made and verified, we consider the hypothesis to be disproven or "falsified." E.g. If the Sun were to rise in the North one day, the example hypothesis given above would be falsified.
Obviously, being falsifiable is different from being false. It would be easy, in principle, to disprove the hypothesis that the Sun always rises in the east, but for all of human history this has never happened, and isn't likely to in the future.
- Falsification is definite - "proof" is unattainable: When a reliable inconsistent observation is made, the hypothesis is definitely falsified - i.e. it's dead dead dead. No amount of consistent observations will bring it back to life. But even if we see ten, a hundred, or a gajillion observations that are consistent with our hypothesis, we can never be completely sure that the next observation won't falsify it. Thus, one never definitively "proves" a scientific hypothesis.
- Statistical qualification: You may consider the foregoing to be an oversimplification. Well, OK. In our imperfect world of uncertainty - about the accuracy of observations and the identity of specimens - we usually resort to statistical tests of hypotheses. E.G.: we may say that there is a 95% probability of a hypothesis being falsified. Even in such cases, we frame our statements conceptually in terms of the falsification of a hypothesis, not in terms of proof.
- Non-falsifiable hypotheses: Hypotheses that are inherently impossible to falsify, either because of technical limitations or because of subjectivity. E.g.:
- "Chocolate is always better than vanilla." [subjective].
- "There are living beings in the Andromeda galaxy." [beyond technical grasp]
- A topic for next week. For now, just remember that "Theory" is not a synonym for "hypothesis."
