How the Scientific Method Works
While there’s no single “scientific method” that all scientists follow identically, most scientific investigation follows this general pattern:
- Observation and Question: Science begins with curiosity about the natural world. You observe something interesting or puzzling: Why do some people get sick while others don’t? Why do plants grow toward light? What causes the seasons?
- Background Research Before investigating, scientists examine existing knowledge. This prevents reinventing the wheel and helps position new questions within the broader context of what’s already understood.
- Hypothesis Formation A hypothesis is an educated guess—a proposed explanation that’s both testable and falsifiable. It’s not merely a question but a potential answer that makes specific predictions. For example: “If plants grow toward light because they need light for photosynthesis, then blocking light from one direction should cause plants to grow in a different direction.” Crucially, a good hypothesis predicts something specific that would be observed if it’s true, and something different that would be observed if it’s false.
- Experimental Design This is where scientists design a test of the hypothesis. Good experimental design includes: Control groups: A comparison group that doesn’t receive the experimental treatment, helping isolate what’s actually causing any observed effect Variables: Identifying independent variables (what you change), dependent variables (what you measure), and controlled variables (what you keep constant) Replication: Testing multiple times to ensure results aren’t due to chance Blinding: When possible, neither the subjects nor the experimenters should know which group receives which treatment, preventing bias from affecting results
- Data Collection and Analysis Scientists carefully gather data during experiments and use statistical methods to determine whether patterns in the data are meaningful or could have occurred by chance.
- Conclusion Based on the evidence, scientists determine whether the data supports or refutes the hypothesis. If the hypothesis is supported, this doesn’t prove it’s true—it simply means it survived this test. If the hypothesis is refuted, it must be modified or abandoned.
- Peer Review and Publication Scientists write up their methods, data, and conclusions and submit them for publication. Other experts evaluate the work for errors, biases, or flawed reasoning before it’s accepted.
- Replication by Others Other scientists attempt to reproduce the findings. Only after multiple independent teams have reproduced results does the scientific community begin to accept a claim as reliable.
- Theory Formation When a hypothesis has been repeatedly supported across many experiments and contexts, and when it connects with and explains other established findings, it may become part of a broader scientific theory. Despite popular usage, in science a “theory” isn’t a guess—it’s a well-substantiated explanation that’s been rigorously tested and has withstood attempts to disprove it.
Observation and Question: Science begins with curiosity about the natural world. You observe something interesting or puzzling: Why do some people get sick while others don’t? Why do plants grow toward light? What causes the seasons?
Background Research Before investigating, scientists examine existing knowledge. This prevents reinventing the wheel and helps position new questions within the broader context of what’s already understood.
Hypothesis Formation A hypothesis is an educated guess—a proposed explanation that’s both testable and falsifiable. It’s not merely a question but a potential answer that makes specific predictions. For example: “If plants grow toward light because they need light for photosynthesis, then blocking light from one direction should cause plants to grow in a different direction.” Crucially, a good hypothesis predicts something specific that would be observed if it’s true, and something different that would be observed if it’s false.
Experimental Design This is where scientists design a test of the hypothesis. Good experimental design includes: Control groups: A comparison group that doesn’t receive the experimental treatment, helping isolate what’s actually causing any observed effect Variables: Identifying independent variables (what you change), dependent variables (what you measure), and controlled variables (what you keep constant) Replication: Testing multiple times to ensure results aren’t due to chance Blinding: When possible, neither the subjects nor the experimenters should know which group receives which treatment, preventing bias from affecting results
Data Collection and Analysis Scientists carefully gather data during experiments and use statistical methods to determine whether patterns in the data are meaningful or could have occurred by chance.
Conclusion Based on the evidence, scientists determine whether the data supports or refutes the hypothesis. If the hypothesis is supported, this doesn’t prove it’s true—it simply means it survived this test. If the hypothesis is refuted, it must be modified or abandoned.
Peer Review and Publication Scientists write up their methods, data, and conclusions and submit them for publication. Other experts evaluate the work for errors, biases, or flawed reasoning before it’s accepted.
Replication by Others Other scientists attempt to reproduce the findings. Only after multiple independent teams have reproduced results does the scientific community begin to accept a claim as reliable.
Theory Formation When a hypothesis has been repeatedly supported across many experiments and contexts, and when it connects with and explains other established findings, it may become part of a broader scientific theory. Despite popular usage, in science a “theory” isn’t a guess—it’s a well-substantiated explanation that’s been rigorously tested and has withstood attempts to disprove it.
The Difference Between Hypothesis, Theory & Law
A factis an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true.” Truth in science, however, is never final and what is accepted as a fact today may be modified or even discarded tomorrow. Facts can be used to make reliable predictions about future outcomes.
A hypothesisis a testable prediction or proposed explanation for a specific observation.
A theory is a comprehensive explanation for a wide range of phenomena, supported by substantial evidence from multiple sources. Evolution, gravitation, and germ theory are theories which means they’re as close to “proven” as anything can be. They’re called theories not because they’re uncertain, but because they’re explanatory frameworks.
A law is a description of a pattern observed in nature, often expressed mathematically, but without necessarily explaining why the pattern exists. Newton’s law of gravitation describes how objects attract each other, but doesn’t explain what gravity is. Einstein’s theory of general relativity provides that explanation.
