Friday, September 3, 2021

The Nature of Science

Your assignment is to read this post and the additional readings available via links at the bottom of this post.

Understanding the Nature of Science is probably one of the most important things you can learn from this class. We live in a world where science and its products are around us, in us, and on us daily. As a result, it is important that we understand what science is and what it is not so that we can be informed about the world around us and in the choices we make. Below is an article from 
UC Berkeley's Nature of Science webpage. It is very well written.

Science Asks Three Basic Questions

1.       What’s there?The astronaut picking up rocks on the moon, the nuclear physicist bombarding atoms, the marine biologist describing a newly discovered species, the paleontologist digging in promising strata, are all seeking to find out, “What’s there?”
2.      How does it work? A geologist comparing the effects of time on moon rocks to the effects of time on earth rocks, the nuclear physicist observing the behavior of particles, the marine biologist observing whales swimming, and the paleontologist studying the locomotion of an extinct dinosaur, “How does it work?”
3.      How did it come to be this way?Each of these scientists tries to reconstruct the histories of their objects of study. Whether these objects are rocks, elementary particles, marine organisms, or fossils, scientists are asking, “How did it come to be this way?”

Science Works in Specific Ways

The purpose of science is to learn about our universe. The joy of science emanates from the freedom to explore and wonder. However, in order to maximize the probability that in the end we get things right, science follows sensible guidelines. It is important to keep in mind certain fundamentals:

  • Science relies on evidence from the natural world and this evidence is examined and interpreted through logic.
  • Creative flexibility is essential to scientific thinking, however science follows a process guided by certain parameters.
  • Science is embedded within the culture of its times.
Understanding how science works allows one to easily distinguish science from non-science. 

Science Has Principles

Science seeks to explain the natural world and its explanations are tested using evidence from the natural world. Birds and lizards are known to exist in nature and therefore fall within the scope of science. Elves and gnomes are great fun to read about and even to enjoy as statues in our gardens, but they do not dwell in the natural world. That means they are not appropriate for scientific study. The basis of any scientific understanding is information gleaned from observations of nature.

Science assumes that we can learn about the natural world by gathering evidence through our senses and extensions of our senses. A flower or a rock can be directly observed with no special aids. But using technology, we can expand the realm of human senses to observe such invisible phenomena as electricity and magnetic fields, and objects such as bacteria and faraway galaxies. Dreams, apparitions and hallucinations, on the other hand, may seem real but they do not arise from our senses and are not even extensions of our senses. The ultimate test of any conceptual understanding exists only in real materials and observations. Evidence is the basic stuff of science. Without evidence there is only speculation.

Science Is a Process

Scientific ideas are developed through reasoning, rejecting the ones that fail the test.
Scientific explanations are evaluated using evidence from the natural world. That evidence may come from various sources: a controlled lab experiment, a study of anatomy, or recordings of radiation from outerspace, to name just a few. Explanations that don’t fit the evidence are rejected or are modified and tested again. Inferences are logical conclusions based on observable facts. Much of what we know from scientific study is based on inferences from data, whether the object of study is a star or an atom. No person has ever seen inside an atom, yet we know, by inference, what is there. Atoms have been disassembled and their components determined. The history of life on Earth has likewise been inferred through multiple lines of evidence.

Scientific claims are based on testing explanations against observations of the natural world and Scientific claims are subject to peer review and replication.
Peer review is an integral part of genuine scientific enterprise and goes on continuously in all areas of science. The process of peer review includes examination of other scientists’ data and logic. It attempts to identify alternative explanations, and attempts to replicate observations and experiments

In the marketplace of ideas, the simplest explanation has the advantage. This principle is referred to as parsimony.
Consider these observations:

  • A close look at snails, nautiloids, squids, octopi and cuttlefish reveals the basic similarity of the body form of each (see below). 

  • The shell of a nautilus and its extinct relatives, the ammonites, is very similar to the shell of a snail.
  • The tentacles of an octopus, when carefully examined, can be seen to be a modified snail's foot.
  • The stomachs of all members of this group have the same arrangement of parts.
One possible explanation is that these animals have independently acquired equivalent organs through a remarkable series of coincidences, but the most likely explanation is that these animals inherited similar organs through common ancestry. That is parsimony.

There is no such thing as “THE Scientific Method.”
If you go to science fairs or read scientific journals, you may get the impression that science is nothing more than “question-hypothesis-procedure-data-conclusions.”

But this is seldom the way scientists actually do their work. Most scientific thinking, whether done while jogging, in the shower, in a lab, or while excavating a fossil, involves continuous observations, questions, multiple hypotheses, and more observations. It seldom “concludes” and never “proves.”
Putting all of science in the “Scientific Method” box, with its implication of a white-coated scientist and bubbling flasks, misrepresents much of what scientists spend their time doing. In particular, those who are involved in historical sciences work in a very different way—one in which questioning, investigating, and hypothesizing can occur in any order.

Theories are central to scientific thinking. 
Theories are overarching explanations that make sense of some aspect of nature, are based on evidence, allow scientists to make valid predictions, and have been tested in many ways. Theories are supported, modified, or replaced as new evidence appears. Theories give scientists frameworks within which to work. Major theories of science, such as the cell theory, gravitational theory, evolutionary theory, and particle theory, are all big ideas within which scientists test specific hypotheses.

The scientific definition of “theory” should not be confused with the way the term is commonly used to mean a guess or a hunch. In science, a theory means much more and is far more well-founded. The “Theory of Evolution” is an evidence-based, internally consistent, well-tested explanation of how the history of life proceeded on Earth—not a hunch. Understanding the role of theory in science is essential to scientists and vital to the informed citizen.



Characteristics of Science

Conclusions of science are reliable, though tentative. 
Science is always a work in progress, and its conclusions are always tentative. But just as the word “theory” means something special to the scientist, so too does the word “tentative.” Science’s conclusions are not tentative in the sense that they are temporary until the real answer comes along. Scientific conclusions are well founded in their factual content and thinking and are tentative only in the sense that all ideas are open to scrutiny. In science, the tentativeness of ideas such as the nature of atoms, cells, stars or the history of the Earth refers to the willingness of scientists to modify their ideas as new evidence appears.

Science is not democratic.
Scientific ideas are subject to scrutiny from near and far, but nobody ever takes a vote. If the question of plate tectonics had been decided democratically when it was first presented in the early twentieth century, we would, today, have no explanation for the origins of much of Earth’s terrain. Scientific ideas are accepted or rejected instead on the basis of evidence.


Science is non-dogmatic.
Nothing in the scientific enterprise or literature requires belief. To ask someone to accept ideas purely on faith, even when these ideas are expressed by “experts,” is unscientific. While science must make some assumptions, such as the idea that we can trust our senses, explanations and conclusions are accepted only to the degree that they are well founded and continue to stand up to scrutiny.

Science Exists in a Cultural Context

Science is not always a direct ascent toward the truth.
Despite the meticulous efforts of those who practice it, science sometimes proceeds in lurches and false starts. In some cases, scientific ideas that dominated a particular time were later recognized as inaccurate or incomplete.

  • Before Galileo challenged the system, geocentrism was the rule. The geocentric model of the Universe persisted for centuries. Eventually, people came to accept that the Earth is not the center of the Universe.
  • Speciation was first described as a gradual process, but in recent years it has become clear that under some conditions speciation can occur relatively rapidly.
  • Alfred Wegener’s ideas about continental drift were not taken seriously until viable mechanisms for moving continents began to be recognized.
Science corrects itself.
Sometimes people make mistakes. Occasionally scientists are swept up in a current of ideas that leads them astray. But errors, misconceptions, and misdirections are corrected by the scientific community itself. Sometimes corrections take years, decades, or even centuries. Improved understanding may result from new technology or changing perspectives, but sooner or later a closer approximation of the truth appears. The fact that old hypotheses fall and new ones take their place does not mean that science is invalid as a way of gathering knowledge. Plasticity of thought is the very essence of the scientific process. For example, within the past 100 years, textbooks have gone from grouping all living things into two kingdoms, to portraying the connectedness of life as three domains.

Science is a human endeavor.
All human frailties are present among scientists. These include:

  • Falling in love with one’s own hypothesis and becoming so attached to it that one refuses to consider new or conflicting data. The cold fusion episode of the 1990s, which implied unlimited energy from a low-temperature version of hydrogen fusion, should serve as a warning to would-be instant scientific heroes.
  • Being drawn in by preconceptions
    A century ago people visualized the human ancestor with bent legs, club in hand, but with enough gray matter to make tools and control fire. “Cave man” cartoons continue to preserve this misperception. But, discoveries in recent decades, such as Australopithecus afarensis, show that even very early human ancestors stood upright, had feet and legs much like ours, but had brains relatively little larger than those of chimpanzees. Science, sooner or later, overcomes prejudices and misapprehensions that are due to cultural influences and personal bias. That is one of the powers of the scientific enterprise.


Key Concepts in the Process of Science

(from The Process of Science, Carpi and Eggar, 2011)
  1. Science is a process of investigation into the natural world and the knowledge generated through that process.
  2. Scientists use multiple research methods to study the natural world.
  3. Data collected through scientific research must be analyzed and interpreted to be used as evidence.
  4. Scientific theories are testable explanations supported by multiple lines of evidence.
  5. Scientific knowledge evolves with new evidence and perspectives.
  6. Science benefits from the creativity, curiosity, diversity, and diligence of individuals.
  7. Science is subject to human bias and error.
  8. The community of science engages in debate and mitigates human errors.
  9. Uncertainty is inherent in nature, but scientists work to minimize and quantify it in data collection and analysis.
  10. Scientists value open and honest communication in reporting research.
  11. Science both influences and is influenced by the societies and cultures in which it operates.
  12. Science is valuable to individuals and to society.

Additional Readings:
The Myths of Science
The Nature of Science by the Geological Society of America (GSA)
Historical science, experimental science, and the scientific method
Nature of Science by the American Academy for the Advancement of Science