Comprehensive Notes on the Nature of Science

Assumptions of Science

Scientists assume specific causes for observed events, rejecting supernatural explanations.
Humans can identify these causes despite imperfections.
General rules or patterns describe observations, assuming an orderly universe with reliable physical laws (e.g., gravity).
Repeated events likely have the same causes; experiments should yield consistent results across time and locations.
Perceptions are not individualistic; different people experience the same universe.
Fundamental rules of nature are universal.
From a Christian worldview, these assumptions align with a belief in a created, orderly universe.

Science is a process for solving problems and understanding nature through testing.
It involves:
- Forming hypotheses (possible solutions).
- Rigorous testing.
- Continual checking.
- Modifying unsupported conclusions.
Data rules: ideas must change if experimental evidence doesn't support them.

Observation: Using senses (or extensions) to record events.
- Involves careful, thoughtful recognition, often with rigorous recording and measurement.
Questioning: Asking why and how events occur (e.g., why one plant grows taller).
Exploring Sources: Reading literature to gain more information; finding if the question has already been answered.
Forming a Hypothesis: Proposing tentative answers or explanations; an educated guess.
- A testable statement that answers a question or explains an observation.
- Must be specific, logical, account for current information, and be testable.
- The simplest hypothesis with the fewest assumptions is preferred.

A recreation of an occurrence to test a hypothesis.
Controlled Experiment: All aspects are kept constant except for one variable.
- Experimental Group: The group where a variable is altered (e.g., receiving a new medicine).
- Control Group: The group where the variable is not altered; receives a placebo to avoid influencing effects.
Independent Variable: The variable altered in the experiment.
Dependent Variables: Variables that change in response to independent variables; documented as data.
Data is analyzed and hypotheses are either rejected, revised, or supported.
Sample Experiment:
- Hypothesis: Adding fertilizer helps pea plants grow taller.
- Experimental Group: Pea plants given fertilizer.
- Control Group: Pea plants not given fertilizer, but given equal water.
- Independent Variable: Presence or absence of fertilizer.
- Dependent Variable: Height of pea plants after thirty days.
- Data Analysis: Comparing average heights using statistical tests.
Conclusion: If pea plants with fertilizer are taller, the hypothesis is supported.
Use large numbers of subjects (e.g., 30-100 pea plants).
Repeat experiments, ideally by different researchers.
Test validity statistically and scrutinize results.

A hypothesis supported by ample experimental data leads to a theory or a law.
Theory: A widely accepted, plausible generalization explaining why things happen (e.g., germ theory of disease).
- Germ theory states infectious diseases are caused by microorganisms.
Law: A uniform or constant fact of nature describing what happens (e.g., all living things come from pre-existing living things).
- Describes what happens, not why.
Recap:
- Hypothesis: A logical, testable prediction without experimental evidence.
- Theory: A hypothesis continually supported by experimental evidence, explaining why things happen.
- Law: A broad statement describing what happens in nature, based on experimental evidence.
Theories and laws are supported by extensive experimental evidence.

Science: Continually challenges and tests principles to determine cause-and-effect relationships.
- Examples: biology, physics, chemistry, astronomy.
Non-Science: Often cannot directly establish hypotheses or cause-and-effect relationships through experiments.
- Examples: history, literature, philosophy, art, sociology.
Similarities: Both use facts, make predictions, and form theories/rules.
Difference: Only sciences conduct experiments to test hypotheses and theories.
Example:
- Astronomy (Science): Uses facts, makes predictions about planetary positions, forms theories about orbits, and changes theories based on experimental data.
- Astrology (Non-Science): Uses facts (planetary positions), makes predictions about the future, has rules, but does not change rules when predictions are wrong.

False science that deceptively uses scientific language to appear valid.
Often seen in marketing claims of nutritional supplements without experimental evidence.
Claims may be made by celebrity doctors or scientists that go beyond existing evidence.
Always check for excellent experimental evidence published in peer-reviewed journals and repeated under different conditions.
Reject pseudoscience.
Distinguish between science (experiments), non-science (arguments), and pseudoscience (false representation of science).