The Scientific Method

Science is the most reliable method humans have developed for understanding the natural world. It is not a collection of facts — it is a process for generating, testing, and refining knowledge.

What Makes Something “Scientific”?

Science is defined by its method, not its subject matter. A field of inquiry is scientific if it:

1. Makes testable predictions (hypotheses)
2. Gathers empirical evidence (observable, measurable data)
3. Subjects claims to peer review (other experts check the work)
4. Is falsifiable — meaning it’s possible, in principle, to prove it wrong

This last point is key. A claim that can never be disproven is not scientific — it’s unfalsifiable. Science does not claim to answer questions beyond the empirical, like “Is life meaningful?” or “Does God exist?” — those are philosophical or religious questions.

The Process

1. Observation — notice something interesting or puzzling in the world
2. Question — formulate a specific question about it
3. Hypothesis — propose a testable explanation
4. Experiment — design and conduct a test; collect data
5. Analysis — examine the results; does the data support or contradict the hypothesis?
6. Conclusion — draw conclusions; acknowledge limitations
7. Peer Review / Replication — other scientists repeat the process to verify

Scientific Theories vs. Everyday “Theories”

In everyday speech, “theory” means a guess. In science, it means something very different:

A scientific theory is a well-tested, widely accepted explanation of a broad category of observations, supported by substantial evidence.

Examples:

• The Theory of Evolution — explains how life diversifies over time through natural selection
• The Theory of Gravity — explains how masses attract each other
• Germ Theory — explains that many diseases are caused by microorganisms
• The Big Bang Theory — explains the origin and expansion of the universe

These are not guesses. They are among the most rigorously tested ideas in human history.

What Science Cannot Do

• Science cannot prove something is true with absolute certainty — it can only say “the evidence strongly supports this”
• Science cannot answer questions of meaning, purpose, or morality directly
• Scientists are humans and can be biased — this is why peer review and replication matter so much

The Branches of Science

Related: Physics Basics | Biology | Chemistry | Climate & Environment | Critical Thinking