The two words theory and hypothesis often get mixed up. The difference between them may not seem important, but it is.
A theory is a collection of ideas or propositions proved by logic and the accumulation of facts and justifiable assumptions. Theories are held to be true, but they can, and sometimes are, proven wrong by the discovery of new information.
For instance, before Christopher Columbus sailed to North America, western Europeans believed the theory that Earth was flat. Columbus’s new information proved this theory to be wrong.
A hypothesis is a possible explanation arrived at by studying facts, using logic and assumption, but it is still in a formative stage. Over time, and generally through experimentation, hypotheses that are proven to be true from all we know become theories.
Scientists commonly set forth a hypothesis and then go about trying to prove whether it is right or wrong. They might say, “It’s an idea. Let’s check it out.”