What is a Theory?
The word “theory” has multiple definitions. Colloquially, “theory” can mean conjecture or an idea that hasn’t been proven yet. In the arts and sciences, however, a theory is not a guess but the explanation of a body of facts.
A Series of Theories
Colour theory describes how colours relate to one another. You probably learned colour theory in school with the colour wheel. Musical theory describes the ways that musical notes relate to each other.
Cell theory explains how cells are structured and how they divide. Germ theory explains how bacteria causes disease. Atomic theory explains how atoms are structured. Modern society is built on these ideas.
Theories & Laws
A law is a fundamental statement of scientific truth. It’s at the base of scientific knowledge. A theory is as good as it gets for a scientist. Theories do not become laws when they are proven.
In the familiar story, Sir Isaac Newton observed an apple falling and concluded that the Earth – and everything else that has mass – has a special pull that drags objects toward it. Still, Newton had a problem. He couldn’t explain how the force worked. That gravity existed everywhere and was holding the planets in place he was sure, but he didn’t know how.
Albert Einstein proposed the theory of General Relativity in 1915. Einstein’s theory explained the natural phenomenon that we call gravity. Space-time, he said, is like a fabric. The fabric is warped by the mass of objects. Einstein’s theory explains Newton’s law – and a few other fundamental laws as well.