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Science Communication LOLO.00.037 www.ut.ee/BG/scom. Session 8 Reflections on the Nature of Science. Science is only the set of findings called scientific knowledge. Science is an organi s ation of our knowledge to help us learn about nature.
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Science CommunicationLOLO.00.037www.ut.ee/BG/scom Session 8 Reflections on the Nature of Science
Science is only the set of findings called scientific knowledge. Science is an organisation of our knowledge to help us learn about nature. Traditional v Contemporary Modelofthe Nature of ScienceTRADITIONAL CONTEMPORARY
Traditional versus Contemporary 4.2 Although science is the pursuit of truth, it is never known whether the truth has been attained.
Additional Contemporary views 5.1. Science is a competitive enterprise. 5.2. The popularity of scientific knowledge is directly related to the prestige of the peoplewho originated that knowledge. 5.3. The ease with which a scientist accepts knowledge is directly related to how closethe scientist’s paradigm (research program, etc.) and the knowledge paradigm are toeach other.
4. Scientific knowledge is proven or disproven owing to the direct influence of observations. 5.1. Scientific knowledge is unchanging. 5.2. Scientific data must not be interpreted by the scientist. 4. Scientists create knowledge based on prior knowledge, observation, and logic. 5.1. The tentativeness of knowledge is related to how much people work on it. 5.2. The truth is defined as an accurate description of nature.
1. A scientist evaluates scientific claims exclusively through empirical evidence. 2. All actions of a scientist are assumed to be open-minded and objective. 3. A scientist is someone who uses the traditional scientific method. 1. The primary act of a scientist is often a leap of imagination or creativity. 2. A scientist interprets results based on prior knowledge, observation, logic, and socialfactors. 3. Scientists create theories based on prior knowledge, observation, and logic. Role of Scientists
4. A scientist strives to discover the absolute truth. 5.1. Scientists must avoid being influenced by anything outside of “pure” science. 5.2. Scientists must report data exactly as their senses perceive it. 4. Ascientist works within the scientific community evaluating& contemplating the workof other scientists. 5.1. Scientists make decisions before inquiry, based on prior knowledge, observation, logic,and social factors. 5.2. A scientist is someone who is curious. 5.3. Scientists communicate with other members of the community. 5.4. A scientist is influenced by past research. 5.5. The first inclination of a scientist is to try and integrate new knowledge into oldknowledge.
6. Science relies on precise control of experiments (and match with prediction) for proof. 7. The use of the traditional scientific method is necessary to discover and validate theories. 8. There is a single method for doing science. 6. Scientists are not compelled to use the traditional scientific method. 7. There is no single scientific method. 8. Methods used by scientists depend on circumstances.
What is ‘the Scientific Method’ ? The traditional scientific method involved • Identifying a research question • Putting forward a hypothesis • Planning an experiment/intervention • Determining the parameters of the expt/intervention • Carrying out the expt/intervention, collecting data • Recording and interpreting/analysing the data • Presenting outcomes and drawing conclusions
1. The scientific method is a step-by-step process. 2.1. The method must be planned out in advance of the inquiry. 2.2. When a scientist uses the traditional scientific method correctly, the results are truewithout doubt. 1.1. Knowledge can be gained by means other than the scientific method. 1.2. Scientists can adjust their method of inquiry in the middle of an investigation andstill obtain valid results. 1.3. The traditional scientific method is simply one possible guide for inquiry.
Theories are based directly on observation. New theories are improvements over old theories because observations improve andincrease over time. An entire theory is falsified if subject to a single contradictory fact. 1. Observations are theory laden. 2. Theories are the inventions of scientists. 3. The occurrence of a contradictory fact does not necessarily compel the abandonmentof a theory. Theories in the Nature of Science
4. A theory is a hypothesis that has been proven to be correct. 5. Old theories are of no use to scientists. 4. Theories are tools used todescribe, explain, and predict scientific phenomena. 5. Theories fit within certainparadigms. 6.1. A scientist’s initial notions of where to start an inquiry are theory laden. 6.2. Theories are validated by their connection to other, generally accepted theories. 6.3. Observations are influenced by social factors.
Making false assumptions • While the scientific process follows an inherent logic and links observations with inference, it also builds on theories and utilises laws to illustrate patterns. • But what about the making of assumptions in making observations, carrying out interpretations, or in deriving theories. • The following tries to illustrate this aspect.
STORY 1 There is a cabin on the side of a mountain. Three people are inside and they are dead. How did they die? Answer: They were killed in a plane crash The three people were the pilot, co-pilot, and navigator. They crashed in snow storm. False Assumption: That the cabin was a mountain cabin. It was actually the cabin of a jetliner.
STORY 2 It is a hot August afternoon. The location is the living room in an old Victorian mansion. The 7-foot (2m) window is open and the curtains are blowing in the breeze generated by the thunderstorm that just passed. On the floor lie the bodies of Bill and Monica. They are surrounded by puddles of water and broken glass. Please close your eyes and picture the scene. Now change the picture. Neither Bill nor Monica has any clothing on. How did they die? Answer: They suffocated. The storm winds blew open the window, which knocked their fish bowl off the table, and it crashed onto the floor. False assumption: That Bill and Monica are human. They are actually goldfish.
STORY 3 A man is walking down the street, sees a bar and enters. He asks the bartender for a glass of water. The bartender pulls out a gun and points it at him. The man says “Thank you” and leaves the bar. What happened? Answer: The man who asked for the glass of water had the hiccups. The bartender pulled the gun to scare the hiccups away. False Assumption: That the bartender pulled the gun in order to kill the man.
STORY 4 A woman leaves home and makes three left turns. She returns home again. On the way, she passed two women with masks. Who were the two women? Answer: The umpire and the catcher. False Assumption: That the woman was walking on city streets. She really is on a baseball field
STORY 5 A man and his son were rock climbing on a particularly dangerous mountain when they slipped and fell. The man was killed, but the son lived and was rushed to a hospital. The old surgeon looked at the young man and declared, "I can't operate on this boy: he is my son." How can this be? Answer: The old surgeon was the boy's mother False Assumption: That the surgeon was a man.
STORY 6 Preston and his men searched the frozen tundra for escaped convict Ben Barker. Just as they were about to give up, one of Preston's men spotted a body. Barker was found lying dead in the snow. There were no tracks leading to or from the body. The cause of death was partially due to the unopened pack on his back. Barker did not die of thirst, hunger, or cold. What was in Barker's pack that led to his death? Answer: An unopened parachute. False Assumption: That Barker’s “pack” was a backpack, not a parachute pack. Also, he had arrived there somehow by land, not by air.
STORY 7 Two train tracks run parallel to each other, except for a short distance where they meet and become one track over a narrow bridge. One morning, a train speeds onto the bridge. Another train coming from the opposite direction, also speeds onto the bridge. Neither train can stop on the short bridge, yet there is no collision. How is this possible? Answer: The trains were crossing the bridge at different times of the morning. False Assumption: Sounds like the two trains had arrived there at the same time; it was just the same morning.
STORY 8 Justin Summers owns a vacation house in northern Ontario which has an A-shaped roof. One side of the roof faces north and the other side faces south. The prevailing winds from the north are usually quite strong. The strange thing is that the stronger the north wind blows, the stronger the resulting updraft on the south side of the roof. Therefore, if a rooster was to lay an egg on the peak of the roof during a strong northerly wind, on which side should the egg fall most of the time? Answer: Roosters don't lay eggs. False Assumption: That the rooster, being a chicken, was a hen.
STORY 9 There is an ancient invention still used in some parts of the world today that allows people to see through walls. What is it? Answer: Windows. False Assumptions: The walls are totally solid and opaque. The walls are not part of a house. Somehow, windows weren’t “invented”. Windows aren’t that ancient. “Some parts of the world” means only a few places, not commonly found.
STORY 10 Sly Hand, the famous magician, claims he can tell the score of any football game before it even starts. Many think he is psychic and possesses supernatural powers. How is it that he can be accurate about the score 99 percent of the time? Answer: There really is no magic. The score of any football game before it starts is always “zero to zero”. False Assumption: That the “score” was the final score. Also, we don’t assume any score exists before the game begins.
STORY 11 It is a stormy, snowy day. There is a man dead inside a shack. There are no windows and the only door is locked from inside. There is no way in or out. The man has a stab wound. There is a puddle of water and blood next to him. How did he die? Answer: He stabbed himself with an icicle! False Assumption: That the water was always liquid, and certainly not in the form of an icicle, not to mention that suicide with an icicle is not very common!
1. Scientific laws are found directly in nature. 2. Scientists interpret the laws found in nature. 3. Scientific laws can be proven to be absolutely true. 4. Laws are proven theories. 1. Laws are created by scientists. 2. Laws are validated within the scientific community. 3. Laws are a scientist’s best attempt to explain some part of nature. Laws in theNature of Science
Examining a Law • Volume is directly proportional to temperature • V proportional to T i.e. V = constant x T • Or V/T = constant • www.chm.davidson.edu/ChemistryApplets/GasLaws/CharlesLaw.html
Facts • In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as "true." • Truth in science, however, is never final, and what is accepted as a fact today may be modified or even discarded tomorrow.
Hypotheses • A tentative statement about the natural world leading to deductions that can be tested. • If the deductions are verified, it becomes more probable that the hypothesis is correct. If the deductions are incorrect, the original hypothesis can be abandoned or modified. • Hypotheses can be used to build more complex inferences and explanations.
Laws and Theories • Laws describe relationships, observed or perceived, ofphenomena in nature. • Theories are inferred explanations fornatural phenomena and mechanisms for relationships amongnatural phenomena. • Hypotheses in science may lead to either theories or laws with the accumulation of substantial supportingevidence and acceptance in the scientific community. Theoriesand laws do not progress into one and another.They are distinctly and functionallydifferent types of knowledge.
Back to the Questionnaire • Questions 5, 6, 7 which were asking about Theories and Laws
Interpretation of Qu 5 • Are scientific theories discovered ? (A,B,C) • Are scientific theories invented ? (D,E,F)
Interpretation of Qu 6 • Are theories related to laws ? (A) • Are scientific laws discovered ? (A,B,C) • Are scientific laws invented ? (C,D,E)
Interpretation of Qu 7 • Are laws more definite than theories ? (A,B,C) • Do theories become laws if there is sufficient evidence? (B, • Or is it that theories and laws cannot be compared ? (D)
Discuss Nature of Science related toSocially and culturally embedded,Subjectivity,Creativity, Tentativeness, Observation and Inference Do we now have some ideas how to describe the Nature of Science ?
Aspects of the Nature of Science Socially and culturally embedded Science is a human endeavour and is influenced by the society and culture in which it is practiced. The values of the culturedetermine what and how science is conducted, interpreted,accepted, and utilised.
Subjectivity • Science is influenced and driven by the presently accepted scientific theories and laws . • The development of questions, investigations, and interpretations of data are filtered through the lens of current theory. • This is an unavoidable subjectivitythat allows science to progress and remain consistent, yet alsocontributes to change in science when previous evidence isexamined from the perspective of new knowledge. • Personalsubjectivity is also unavoidable. • Personal values, agendas, and prior experiences dictate what and how scientists conduct their work.
Creativity • Scientific knowledge is created from human imaginations andlogical reasoning. • This creation is based on observations andinferences of the natural world.
Tentativeness Scientific knowledge is subject to change with new observations and with the reinterpretations of existing observations. Scientific knowledge is based on and/or derived from observations of the natural world.
Observation and Inference • Science is based on both observation and inference. • Observationsare gathered through human senses or extensions of thosesenses. • Inferences are interpretations of those observations. • Perspectives of current science and the scientist guide bothobservations and inferences. Multiple perspectives contribute tovalid multiple interpretations of observations.
Consider these two examples • Is the notion that hypothetical particles (tachyons) may travel faster than light a pseudoscientific idea? • Well this speculation was proposed by scientists with perfectly respectable credentials, and other respectable experimenters took time to look for such particles. None have been found. We no longer expect to find any, but we do not consider the idea to have been "unscientific".
Example 2 • Is it scientific to hypothesise that one could build a perpetual motion machine that would run forever with power output, but no power input? • Most scientists would answer "No." • What is the essential difference between these two examples?
Possible responses • In the first case, the hypothetical tachyons would not violate any known principles of physics. • In the second case, a perpetual motion machine would violate the very well-established laws of thermodynamics, and also violate even more basic laws as well, such as Newton's laws, and conservation of momentum and angular momentum.
But are the laws and theories of science sacred? • Of course not; they represent part of the logical structure called "established science" that is the culmination of our accumulated scientific knowledge.
The tentativeness of science, or science is not the truth ! • We fully expect that future discoveries and insights will cause us to modify this structure in some ways. • This won't invalidate the whole of science, for the old laws and theories will continue to work as well as they always did, but the newer structure may have more precision, power, breadth or scope, and may have more appealing conceptual structure. • Such continual evolution and modification of science is gradual and generally changes only a small portion of the vast edifice of science. • Once in a while, a "revolution" of thought occurs causing us to rethink or reformulate a major chunk of science, but even that doesn't make the old formulations wrong within their original scope of applicability.
But ….. • The seekers after perpetual motion are a textbook example of the scientific impulse gone astray. • They exhibit most of the qualities of pseudoscientists as mentioned in session 4.
What is science ? • Science is a mode of generating and evaluating ideas. • It is a way of thinking, knowing, working and communicating about the natural and social world. • It is both rational and subjective, both creative and methodical, both speculative and logical. • Science is about being curious, investigating and testing how the world works.
