“Facts are not science – as the dictionary is not literature” –Martin H. Fischer If science is not facts, what is it?

The Nature of Science

Nature of Science  Science is a process by which we try and understand how the natural world works

Science is NOT…  Collecting or memorizing facts or observations  ALTHOUGH this does help!

Science is a process…  …but not necessarily one “set in stone” system of rules  We use the “Scientific Method” because it is the most commonly observed and used method  This method provides the most understanding and meaning to new scientists

Uncertainty  There is NO certainty in science  There ARE degrees of probability and potential for change  Scientific understanding can ALWAYS be challenged with new evidence  NOTHING in science is ever PROVEN.

Modern science is based on several assumptions…  The world is real and not just our imagination  Humans can accurately perceive and understand the physical universe  Natural processes are sufficient in explaining the natural world  Nature operates in the same way everywhere in the universe and at all times (except where we have sufficient evidence to demonstrate otherwise)

Modern science has limitations…  Observations are limited by human senses  Our senses are unconsciously influenced by previous experience  It is impossible to know if we have observed all possible aspects, controlled all possible variables, or considered every possibility of a phenomenon

Science is contingent knowledge  It is NOT absolute  Based only on available evidence NOT on “proof”  History of science is full of changes in understanding and explanations

Science must follow certain rules  Scientific explanations must be based on careful observations and testing of hypotheses  It must be able to be disproven  Solutions can NOT be based on opinion, popular belief, or judgment  Explanations cannot be based on supernatural forces (because they cannot be disproved)

Science must follow certain rules  All hypotheses are not of equal value  The “best” hypothesis is that which best explains ALL the facts/evidence  Science is NOT democratic or fair

It is also important to point out…  …that science CAN be misused  BUT its limitations are its strengths

The Scientific Method Better than other methods

Observation  What is happening?  Is there anything interesting?

Purpose  What do you want to find out?  What is your goal?

Hypothesis  What do you think will happen?  What is the most probable outcome?  BE CAUTIOUS!

Materials  What things do you need to test your hypothesis?

Procedure  What will you do to test your hypothesis?  This should include an explanation of how you will use the materials  A well designed procedure will include multiple trials

Independent Variable  The variable you are testing  What will you change?

Dependent Variable  What are you measuring?  What is the outcome – what units will your data be in?

Constants  The things that do not change from one trial to the next  What might influence the independent variable that should be maintained?

Control  The standard to which you will compare your experiments

Results  When you did the experiment, what happened?  What did you see, hear, smell, measure?

Conclusion  What did your results mean?  Was your hypothesis correct or incorrect?  Are further experiments needed?  What could have been improved?

Scientific Theory

 A scientific theory is the best fit explanation for a phenomenon that is repeatedly confirmed through observation and experimentation via the scientific method

Criteria for a scientific theory  A theory must be falsifiable  A theory must fit a phenomenon with consistent accuracy  A theory is well supported by many independent strands of evidence, not just one

Criteria for a scientific theory  A theory must fit previous knowledge or experimentation  A theory can be adapted to account for new evidence  A theory must be the simplest explanation – Occam’s Razor

Examples of Scientific Theory  Quantum Theory  Cell Theory  Theory of Evolution  Climate Change  Plate Tectonics

So what’s the difference between a law and a theory?  A law is an obvious generalization that describes a phenomenon  A theory attempts to explain why a phenomenon happens  Both can be disproven if and when new evidence is discovered