Scientific Claims

Scientific Claims

Definition: Understanding how scientific knowledge is structured requires distinguishing between different types of statements and explanations: observations, claims, hypotheses, theories, and laws. Below is a breakdown of these key concepts in the scientific process.

** For general rhetorical claims, see Claim. 

Scientific Observation

An observation is a direct record of a phenomenon using the senses or instruments. It is the foundation of empirical science.

Types of Observations

• Qualitative Observations: Descriptive (e.g., "The sky appears red at sunset").

• Quantitative Observations: Measurable (e.g., "The temperature of the solution increased by 5°C").

Examples

• Astronomers observe that galaxies are moving away from each other, which is measured by redshift.

• Biologists observe that certain bacteria develop resistance to antibiotics over time.

Scientific Claim

A scientific claim is a statement that asserts something as fact based on empirical evidence, logical reasoning, and scientific principles. It is a conclusion drawn from observations, experiments, or research that can be tested and evaluated. A claim may be supported by data but is often subject to challenge, requiring further testing.

Examples

• "Earth's average temperature is rising due to increased CO₂ levels."

• "There is liquid water beneath the ice on Jupiter's moon, Europa."

Scientific Hypothesis

A hypothesis is a testable and falsifiable statement that offers a possible explanation for an observation. It serves as a starting point for experimentation. 

Features of a Hypothesis

• Testable (Can be examined through experiments or observations)

• Falsifiable (It is possible to prove it wrong if contrary evidence is found)

Examples

• "If plants receive more sunlight, then their rate of photosynthesis will increase."

• "The decline of bee populations is linked to pesticide use."

Scientific Theory

A theory is a well-substantiated explanation of natural phenomena based on a broad body of evidence. Theories are developed through repeated testing and refinement. 

Features of a Theory

• They explain observations and experimental results.

• They are based on extensive evidence and peer-reviewed research.

• They can be modified if new evidence contradicts them.

Examples

• Theory of Evolution: Explains how species change over time due to natural selection.

• General Relativity: Describes how gravity affects space-time.

* Misconception: In everyday language, "theory" means a guess. In science, a theory is a thoroughly tested and supported explanation.

Scientific Law

A scientific law is a statement that describes a consistently observed phenomenon in nature, often expressed mathematically. Unlike theories, laws describe rather than explain. 

Theory vs. Law

• A law describes what happens (e.g., gravity makes objects fall).

• A theory explains why it happens (e.g., Einstein’s General Relativity explains gravity)..

Examples

• Newton’s Laws of Motion describe how objects behave under force.

• The Law of Conservation of Energy states that energy cannot be created or destroyed, only transformed.

Scientific Model

A scientific model is a simplified representation of a system or concept used to explain complex phenomena. Models are useful for testing hypotheses and making predictions but may be revised as new data emerges.

Examples

• The Bohr Model of the Atom represents electrons orbiting a nucleus.

• Climate Models predict future temperature changes based on greenhouse gas emissions.

Scientific Paradigm & Shift

A paradigm is a dominant framework within which scientific research operates. 

A paradigm shift occurs when new evidence overturns a widely accepted theory or when discoveries fundamentally change our understanding of the world.

Examples

• The Copernican Revolution replaced the geocentric model (Earth-centered) with the heliocentric model (Sun-centered).

• Plate Tectonics replaced the idea that continents were static.