What's the difference between hypothesis, theory and law? I think I'm confused now because I exactly learned the misconception one as explained below in high school.

According to this university's website it says that what I learned from school is a misconception. Is this explanation generally accepted among the scientists.

MISCONCEPTION: If evidence supports a hypothesis, it is upgraded to a theory. If the theory then garners even more support, it may be upgraded to a law.

CORRECTION: This misconception may be reinforced by introductory science courses that treat hypotheses as "things we're not sure about yet" and that only explore established and accepted theories. In fact, hypotheses, theories, and laws are rather like apples, oranges, and kumquats: one cannot grow into another, no matter how much fertilizer and water are offered. Hypotheses, theories, and laws are all scientific explanations that differ in breadth — not in level of support. Hypotheses are explanations that are limited in scope, applying to fairly narrow range of phenomena. The term law is sometimes used to refer to an idea about how observable phenomena are related — but the term is also used in other ways within science. Theories are deep explanations that apply to a broad range of phenomena and that may integrate many hypotheses and laws. To learn more about this, visit our page on the different levels of explanation in science.


  • 3
    $\begingroup$ I'm voting to close this question as off-topic because it's not a physics question. $\endgroup$
    – ACuriousMind
    Jul 1, 2016 at 11:41
  • 1
  • $\begingroup$ In my experience in physics - just finished undergraduate and am going to graduate next year - they have the following uses. "Hypothesis" is a guess, one which does not follow clearly from agreed-upon information. It is implicit that it will be followed up with investigation to check if it is true. "Theory" and "Law" are used interchangably. Why? Because there is no amount of evidence that can convince us that something won't be proven false in the future - nothing is certain. So "Theory" and "Law" are both just "things which are widely believed to be true". $\endgroup$ Jul 1, 2016 at 13:54
  • $\begingroup$ @user3141592: Most hypotheses formulated by capable scientist follow quite clearly from known things. They are not guesses but deliberate changes in the assumptions that lead to the problems which the hypothesis is trying to resolve. A law is a small part of a theory, so, no, the two are not interchangeable. To be honest, I would expect an undergraduate to know these things. Especially the "belief" bit is highly questionable, unless you are graduating in religious studies? $\endgroup$
    – CuriousOne
    Jul 1, 2016 at 18:25
  • $\begingroup$ @CuriousOne True, theory is usually used for a field like "Quantum Mechanics" or "String Theory". So a law is usually a member of a theory. I should have realized the distinction. On the subject of belief - strictly, one cannot use a stronger word. There is strong indication that laws are true, but there is always room for contradiction in the future. Strictly, one also cannot leave out the possibility of human error in experiment or proof. Therefore the laws of physics are not necessarily "true" in the global sense in which the word is usually used. That said, I would bet money on them. $\endgroup$ Jul 2, 2016 at 20:17