Notes on the Nature and Process of Science

A. Nature of Science

  • What is Science?

    • Definition: ‘the systematic inquiry – Earth

    • Science as a way of knowing and understanding

  • Science is a way of knowing and understanding

    • Focus on the Natural World

    • Observable and measurable (vs. supernatural, which is not detectable)

    • Core activities: Observations, Explanations, Predictions, Testing, Repeatable, Continuous

  • General Underlying Principles of Science

    • Events attributable to natural causes

    • Natural laws apply everywhere

    • Value neutral

  • Science is both a body of knowledge and a process to generate that knowledge

    • Dual nature: a repository of facts and a method for producing more knowledge

  • Science as a body of knowledge

    • Facts arise from observations (repeated and repeatable) ⇒ Data ⇒ Explanations

    • Built from inductive reasoning

    • Supported by evidence: observations and tests of explanations

    • Generalization: conclusions drawn from actual observations

    • Not derived from: intuition, tradition, or common sense alone

  • Facts, Laws, and Theories

    • Facts: Observations (repeated and repeatable)

    • Laws: Describe how events happen

    • Theories: Explain why events happen

  • Theories in Biology

    • Theory of Evolution: Explains what causes evolution to occur

    • Cell Theory: Explains what all living things are made of

    • Germ Theory of Disease: Explains cause of disease

  • Science as a process to generate knowledge

    • Studies can be: Descriptive, Observational, Experimental

    • Knowledge types: Descriptive and Explanatory

  • Process of science (overview of approach)

    • Tests possible explanations via hypotheses

    • Hypotheses are testable predictions

    • Predictions are derived from hypotheses

    • Emphasizes a cycle of observation, explanation, testing

  • Hypothesis and prediction concepts (from the process)

    • Hypothesis: a possible explanation for observed outcomes; testable; can be refuted

    • Predictions: derived from a hypothesis; specific expectations about future outcomes

    • Deductive reasoning: used to generate predictions from hypotheses

    • Example form: If a factor increases, then the observed outcome should increase

    • Notation for prediction: extIfF<br>earrow<br>ightarrowO<br>earrowext{If } F <br>earrow <br>ightarrow O <br>earrow

  • Section summary

    • Science is both a body of knowledge and a dynamic, testable process

    • It relies on natural causes, universal laws, and a value-neutral stance

B. Process of Science

  • Process tests possible explanations

    • Possible explanations are called hypotheses

    • A hypothesis explains the cause of observed outcome(s)

    • A hypothesis must be testable

    • The test must be able to yield an outcome that could falsify the hypothesis

  • Predictions derived from hypothesis

    • Deductive reasoning: from hypothesis to predictions

    • Predictions describe expected future outcomes

    • Specific and directional

    • If/then form: If the factor increases, then the observed outcome should increase

    • Notation for prediction: extIfF<br>earrow<br>ightarrowO<br>earrowext{If } F <br>earrow <br>ightarrow O <br>earrow

  • The Scientific Method (overview of steps)

    • 1) Observation

    • 2) Question

    • 3) Background research

    • 4) Construct a hypothesis

    • 5) Experiment: test your hypothesis

    • 6) Analyze data

    • 7) Draw a conclusion

    • 8) Report results (Was your hypothesis correct?)

    • Defined: Series of steps to collect information or solve problems

    • Detailed steps often listed as:

    • 1) Observation

    • 2) Hypothesis

    • 3) Experimentation

    • 4) Data Analysis

    • 5) Conclusion

  • Process of Science consists of multiple interrelated parts

    • Benefits and outcomes include:

    • Exploration and discovery

    • Testing ideas

    • Community analysis and feedback

    • Resource: Understandingscience.org (Note: ©2008 UCMP, Berkeley and Regents of UC)

  • Hypothesis Testing

    • Directly test predictions derived from the hypothesis

    • Conduct experiments under controlled conditions

    • Researcher manipulates one condition between tested groups

    • All other conditions kept similar between groups

    • Differences attributed to the single changed condition

  • Variables

    • Independent variable: the factor manipulated to test its effect (the cause)

    • Dependent variable: the factor that may depend on the independent variable (the effect)

  • Controls

    • To control: to keep variables unchanged

    • Controlled variable: a variable kept the same

    • Standardized variable: another term for a constant condition

    • Control group: a comparison group where the tested variable is unchanged

  • Other considerations of an experiment

    • Sample size: more individuals or trials increase confidence in results

    • Use statistics to interpret results

    • Use mathematics to determine if there is a real difference between groups

  • Conclusion (nature of science in practice)

    • Science is both knowledge and process that informs our understanding of the natural world

    • Observations can lead to explanations

    • Explanations can be tested via further observations

    • Observations and results of tested explanations are evidence supporting scientific understanding

    • The scientific process is ongoing and updated by new observations, explanations, and tests

  • Connections to wider context

    • Science relies on observable, repeatable evidence and a systematic approach to build reliable knowledge

    • Theories (e.g., Evolution, Cell Theory, Germ Theory) provide frameworks that unify diverse observations

    • Ethical and philosophical stance: value neutrality and methodological rigor guide interpretation of data