1. TOK: Areas of Knowledge
The Natural Sciences

2. Discussion Questions Is science the only road to knowledge?
Does science have a monopoly on truth?
How far do the natural sciences give us certainty?

3. The Natural Sciences Scientific Revolution – 17th Century
Galileo Galilei and Sir Issac Newton
19th Century – Scientists are conscious of their contributions to society.
Promoting their own contributions and creating self-justifying historical pictures
“Cuvier, Humboldt, Ritter, Lyell, Darwin, Comte, and many others were not only aware of being genuine creators and the force behind new scientific developments, they also took active part in contemporary controversies and felt the need, to a greater or lesser extent, to convince the general public of the innovative character of their work.
This led them to write, or rewrite, the history of the discipline, to reveal the obstacles that had been put in the way of the development of that science”(Capel).
Discoveries of the Past 300 Years
Fundamental laws of physics
92 Elements of the Periodic Table
DNA Decoding

4. Natural Sciences Natural Sciences include: Physics Chemistry Biology
What other fields are in the Natural Sciences?

5. The Natural Sciences
Some argue that science is the only road to knowledge
Natural Sciences are the dominant cognitive paradigm (model of knowledge)
Science is not God and has weaknesses and limitations
Scientific beliefs change over time.

6. Discussion Questions
Give some examples of things that were believed to be true by 19th century scientists but which we now know to be false.
Are scientists playing God? How?
What connotations does the word science have for you? Are they positive, negative, or mixed?
How are scientists viewed in popular culture, such as novels and movies? Are they generally seen as heroes or as villains?

7. Natural Sciences and Language
A table from the article “Communicating the Science of Climate Change,” by Richard C. J. Somerville and Susan Joy Hassol, from the October 2011 issue of Physics Today, page 48:

8. Natural Science and Language
What are the implications of the table regarding the scientific community?
How does miscommunication or misinterpretation of language affect knowledge?

9. Natural Sciences
How have advertisers used the language of science to market products?

10. Science & Marketing

11. Science vs. Pseudo-Science
All of the following have been described as scientific:
Acupuncture – needles & pins
Astrology – the stars
Creationism – intelligent design
Crystology – rocks that heal
Feng shui – flow by organization
Graphology - handwriting
Homeopathy – natural herbs
Phrenology – skull study

12. Pseudo-Science (Fake Science)
Some people are willing to subject their beliefs to scientific tests, others simply state their beliefs are scientific.
Racists often claim their beliefs on biological research.
Pseudo-science claims the status of science while lacking its substance.

13. Discussion Questions
What is the difference between astronomy & astrology?
As a scientist, how would you go about trying to test the claims of astrology?

14. Science & Pseudo-Science – The Differences
The main difference is that scientific hypotheses are testable – pseudo-science is not.
Two ways pseudo science is NOT testable:
Vagueness – a genuine scientific claim needs some kind of criteria (preferable measurable).
Ad hoc exceptions – a scientific hypothesis is general in nature – “All swans are white.”

15. Science & Pseudo-Science – The Differences
It will be easy to test a hypothesis if the following are true:
It is clearly stated and makes precise rather than vague predictions.
It does not keep making ad hoc exceptions when it comes across counter-examples.

16. Discussion Question
Which of the following statements makes scientifically testable claims?
In 2016, you may or may not win the lottery.
It always rains on Tuesdays.
We have all lived past lives, but most of us are too unenlightened to remember them.
Real men don’t cry.
Unlike magnetic poles attract each other.
Everyone is selfish.
Acid turns litmus paper red.
Something surprising will happen to you next week.

17. The Scientific Method
What distinguishes science from non-science is a distinctive method.
Science is not so much a fixed body of knowledge as a way of thinking about the world.

18. Discussion Question
How is each of the following similar to scientific activity and how is it different?
Baking a cake by following a recipe.
“Experimenting” with ingredients and making your own recipe.
Collecting and organizing stamps from around the world.
Repairing a car that has broken down.

19. Inductivism
Inductivism is the traditional picture of the scientific method:
Observation
Hypothesis
Experiment
Law
Theory

20. Inductivism
1) Observation – observe and classify data
2) Hypothesis – look for a pattern and make a guess
3) Experiment – test the hypothesis
Controllability – vary only one factor at a time to determine the effect
Measurability – measure relevant variables
Repeatability – experiement can be repeated with same results.

21. Inductivism cont…
4) Law – if the experiment confirms the hypothesis and id is controllable, measurable, and repeatable.
5) Theory – explains and unifies various laws and explains why laws are the way they are and provides focus for further research.

22. The Copernican Revolution
Ptolemy (85-165) – Earth centered theory (geocentric)
Copernicus ( ) – Sun centered theory (heliocentric)
How did each develop their theories?

23. The Copernican Revolution
Observation: new and better observations made Ptolemy’s model more complicated.
Hypothesis: more elegant approach to make the sun the center.
Prediction: Copernicus theorized that Venus becomes a different size through observations at different times of year – Galileo ( ) confirmed this theory.

24. The Copernican Revolution
Law: Johannes Kepler ( ) – developed laws of planetary motion based on Copernicus and Galileo.
Theory: Isaac Newton ( ) – theory of gravity allowed explanation of a wide variety of phenomena

25. The Copernican Revolution
Newtonian physics – there is a force of attraction between objects whose strength is directly proportional to their masses and inversely proportional to the square of the distance between them (if you double the distance between two objects, the gravitational attraction between them will be ¼ of its original strength)

26. The Copernican Revolution
Newtonian physics thus explains many things:
Why an apple falls from a tree
Why people have weight
The movement of the tides
The orbit of the planets

27. The Copernican Revolution
The following points are taken from the Copernican Revolution:
Scientific progress needs a background of careful observation
Technology can extend our powers of observation
Imagination plays a role in the development of new scientific ideas
Mathematics plays a central role in the development of scientific ideas.
Many scientific discoveries are counter-intuitive – go against common sense.

28. Discussion
Try and explain the following to someone who does not know much about physics:
If the earth is round and rotating on its axis, how come it doesn’t feel like we are moving?
If the Earth is round, why don’t people fall off the bottom?
Since birds fly far slower than the Earth rotates, how come they don’t get left behind when they fly in the direction of the rotation (east to west)?

29. Homework 1
Research the placebo effect and give an explanation of it. What is its relevance when we evaluate the claims of alternative medicines?

30. Homework - 2
Each of the following elements below is relevant to the scientific method. Try to put them is sequential order and write a short description about how a scientist typically works.
Experiment, hypothesis, measurement, repeatability, induction, law, observation, theory.

31. TOK II – Areas of Knowledge -
The Natural Sciences – Part II

32. 4 Problems with Observation
Relevance – you must begin with what is relevant and irrelevant to the problem.
Expectations – expectations can influence what we see
Expert Seeing – use of scientific equipment can often further complicate things
The Observer Effect – the act can affect the outcome.

33. Problems with Observation
Relevance – it is always possible to overlook a factor
Expectations – overconfidence
Expert Seeing – observer is only as good as their equipment.
The Observer Effect – the observer changes the experiment – thermometer in the hot tea.

34. Complications of Testing Hypotheses
Confirmation Bias – people look for evidence that confirms and ignore what goes against them.
A good scientist is aware of confirmation bias.

35. Complications of Testing Hypotheses
Background assumptions – we make assumptions that at any time could be false.
Parallax – (ex. Stellar) relative position of stars changes as the earth moves around the sun.

36. Complications of Testing Hypotheses
Many different hypotheses are consistent with a given set of data.
Principle of simplicity – when given two complicated theories which make exactly the same predictions the simpler theory is to be preferred.

37. The Problem of Induction
Inductive reasoning goes from the particular to the general (all metals expand/all mammals are warm blooded)

38. Practical Problems
How many observations should we make until we are entitled to make a generalization?
No “hard or fast rule about “how many?”
We have observed a minute fraction of the universe, yet we apply the laws we have learned to all of the universe.

39. Theoretical Problems
Observation is supposed to be an empirical discipline which makes no claims past what is observed.
Observation is supposed to distinguish science from pseudoscience.

40. Falsification
Karl Popper ( ) – tried to distinguish science from pseudoscience (Marxism/psychoanalysis).
“A theory that explains everything explains nothing” – a scientific theory must put itself at risk to be disproven.

41. Conjectures & Refutations
A conjecture is basically an imaginative hypothesis – no mechanical way of coming up with good hypotheses on the basis of observational data.
A scientific conjecture is testable
Refutation needs only find one instance to disprove a hypothesis.

42. Conjectures & Refutations
Popper believed instead of trying to prove something true, try to find faults instead.
For science to progress it must constantly question shortcomings.
Popper believed that an established theory is the best we have for the time being.

43. Criticisms of Popper Falsification
Conclusive in theory but not in practice
No more conclusive than verification
Finding a single counter-example is not enough to overturn a law of nature.
When a conflict occurs between hypothesis and observation we have a choice to either reject the hypothesis, or we can reject the observation.

44. Examples of Refused abandoned Theories
Newton’s theory of gravity – gravity would cause universe to crunch
Mendeleyev – some atomic weights did not quite fit his model
Darwin – Earth must be 100s of millions of years old to fit his theory even though science at the time put it about 100 million years old.

45. Criticisms of Popper
Auxiliary hypotheses can rescue a falsified theory
Background assumptions could have been wrong or experimental error – hard to disprove hard facts
No such thing as a perfect theory – auxiliary hypothesis.

46. Criticisms of Popper The rationalist strand in scientific thinking
When there is a conflict between observation and hypothesis, there are 3 options:
Reject the hypothesis
Reject the observation
Accept both and form an auxiliary hypothesis
A rationalist sees reason as the main source of knowledge – order to things
An empiricist sees experience as the main source of knowledge.

47. Summary of Popper and Criticisms
Scientific theories can not be conclusively verified because of the problem of induction; and they cannot be conclusively verified because of the problem of induction.
The concept of proof only applies to math and logic.
Science cannot prove things in an absolute sense.

48. Historian/Philosopher of Science
Thomas Kuhn ( )
Historian/Philosopher of Science
Introduce the concept of the paradigm.

49. Science & Society According to Kuhn
Paradigm – an overarching theory shared by a community of scientists, such as physicists, chemists, or biologists, which is used to make sense of some aspect of reality.
i.e. – Newtonian mechanics in physics, Atomic theory in chemistry, & Evolutionary theory in biology.

50. Normal Science
The vast majority of scientists are so busy solving problems within a paradigm they take the actual paradigm for granted.
A scientist cannot endlessly question assumptions
Newton, Dalton, & Darwin were the architects – scientists today are the bricklayers.

51. Scientific Revolutions
A scientific revolution takes place when scientists become dissatisfied with the prevailing paradigm, and put forward a completely new way of looking at things.
The new paradigm replaces the old and normal science begins again.
Ex. Aristotelian Physics replaced Newtonian Mechanics (NM) and NM was replaced by Einstein’s Theory of Relativity.
There is no such thing as a perfect theory in science. .

52. How Rational is Science?
Progress of science is not as rational as sometimes thought.
Sometimes doubt and observations that falsify old paradigms create irrational answers.
Priority Disputes – groundbreaking discoveries that set up paradigms (scientists like celebrity status too!)

53. Assessment of Kuhn – Normal Science
(1) During period of normal science, the paradigm is not questioned – focus is on solving problems. (Popper believed this was false and said that Kuhn was stagnating the science with his approach)
Science should always question – one should not be content to merely solve puzzles.

54. Assessment of Kuhn – Scientific Revolutions
(2) History suggests science is not smooth but rather makes revolutionary jumps.
This position could be false because science is punctuated with periods of intellectual upheaval.
Intellectual upheaval does not mean when one paradigm replaces the old one that it vanishes without a trace
Science progresses towards the truth.
Science is a cumulative way to the future.

55. Assessment of Kuhn – Choosing Between Rival Paradigms
(3) During period of scientific crisis, there is no purely rational way of deciding between rival paradigms.
We should choose between the origin of a belief and its justification.
Origin of belief is of no great consequence.
All that matters is that a belief is testable.

56. Assessment of Kuhn – Choosing Between Rival Paradigms
Every area of knowledge depends on judgment!
We need judgment to decide such things as what factors should or should not be observed, what can be ignored, which hypotheses make sense, what data should be used, and what anomalies to take seriously

57. Science & Truth There is no absolute proof in science.
We can neither conclusively verify or falsify a hypothesis.
We must maintain a critical attitude to our scientific beliefs and be willing to question our assumptions.

58. A Theory of Everything
Some believe that the ultimate goal of science is to discover a theory that is so general that we have a complete understanding of nature.
We will never know everything about nature – it is too complex
We will only be able to make connections to nature and never completely understand it.

59. Science & Scientism
Science is the only way we can make sense of reality and discover the truth.
We can be proud of science’s achievements but it is a fallible human enterprise which may get us closer to the truth but never give us certainty.

60. Conclusion
Science has been responsible for a large body of knowledge in the past 300 years.
Science is limited to our understanding of our world around us.
Dogmatic scientism is static (Kuhn)
Paradigm shifts occur with new knowledge.