Lecture Notes: What is Science? (Part 4)

Key Concepts

• Scientific vs Non-Scientific Concepts
  • Non-Scientific: Ancient Texts, Divine Revelation
    • Personal experiences like visitations from ghosts, angels, etc., are untestable and unverifiable
    • Ancient texts are not inherently correct simply due to their age
  • Scientific Concepts:
    • Need to go through the scientific process
    • Involvement of hunches, insights, and case studies

Hunches and Insights in Science

• Example: Kekulé's discovery of benzene structure through a daydream
• Hunches/insights guide hypothesis development
• Verified through experimentation

Hypotheses

• More than a guess; it's a testable statement predicting a causal link
• Structure: "If-then-because" format
  • Example: Light requirement for plant growth
    • Independent Variable: Amount of light
    • Dependent Variable: Plant growth
    • Explanation: Photosynthesis importance
  • Natural Experiment Example: Gender differences in interest in cars
    • Independent Variable: Gender
    • Dependent Variable: Grand Prix attendance

Experiments to Laws and Theories

• Laws: Statements of relationships without explanations
  • E.g., Newton's laws, Hooke's Law, Mendel's laws
• Theories: Explanatory frameworks supported by multiple lines of evidence
  • E.g., Cell theory, Germ theory, Quantum mechanics
  • Must have predictive power

Weight of Evidence

• Cutting-edge science can present conflicting evidence
• Importance of the weight of evidence perspective

Disagreements in Science

• Encouraged within the scientific community
• Example: Debate on the nature of light (particle vs wave)
  • Led to current understanding of dual nature

Influence of Biases in Science

• Human biases affect how data is interpreted and experiments are conducted
• Peer-review and self-correcting nature balance biases
• Societal influences dictate research focus
  • E.g., Stem cell research delay in the US due to political stance

Mysteries of Nature Yet to Be Solved

• Biology: Vast majority of species yet to be discovered
• Physics: Majority of the universe is dark matter and dark energy
  • Only 0.4% of the universe is observable matter

Final Thoughts

• Carl Sagan's perspective on science

References

• [Speaker's list of references]