Scientific theory

A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method and repeatedly tested and confirmed, preferably using a written, predefined, of observations and experiments. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge.

It is important to note that the definition of a "scientific theory" (often ambiguously contracted to "theory" for the sake of brevity, including in this page) as used in the disciplines of science is significantly different from, and in contrast to, the common vernacular usage of the word "theory". As used in everyday non-scientific speech, "theory" implies that something is an unsubstantiated and speculative guess, conjecture, idea, or, hypothesis; such a usage is the opposite of the word 'theory' in science. These different usages are comparable to the differing, and often opposing, usages of the term "prediction" in science (less ambiguously called a "scientific prediction") versus "prediction" in vernacular speech, denoting a mere hope.

The strength of a scientific theory is related to the diversity of phenomena it can explain, and to its elegance and simplicity (see Occam's razor). As additional scientific evidence is gathered, a scientific theory may be rejected or modified if it does not fit the new empirical findings; in such circumstances, a more accurate theory is then desired. In certain cases, the less-accurate unmodified scientific theory can still be treated as a theory if it is useful (due to its sheer simplicity) as an approximation under specific conditions (e.g., Newton's laws of motion as an approximation to special relativity at velocities that are small relative to the speed of light).

Scientific theories are testable and make falsifiable predictions. They describe the causal elements responsible for a particular natural phenomenon, and are used to explain and predict aspects of the physical universe or specific areas of inquiry (e.g., electricity, chemistry, astronomy). Scientists use theories as a foundation to gain further scientific knowledge, as well as to accomplish goals such as inventing technology or curing disease.

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