English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

An experiment is normally intended to test a hypothesis. Is there a noun or phrase to describe an experiment with no hypothesis -- i.e. doing something just to 'see what happens'?

(A convincing neologism would be acceptable: e.g. exploriment)

EDIT: It's been pointed out that one can think of some generalised hypothesis ('something interesting will happen') for any experiment. So to refine the question a bit: what's an experiment without a specific hypothesis?

EDIT2: Thanks for the helpful suggestions so far, which have clarified things, although sadly none have nailed it for me yet: perhaps English doesn't have a word with the connotation I'm looking for.

However I'm surprised that some of the answers have implied that there's something trivial, invalid or unscientific about experimenting without a testable hypothesis: i.e. it's "just playing about" or "just demonstration". This made me think about three types of experiment:

(A) I do something (heat water) to test a specific hypothesis (does water boil at 100°C?); 
(B) I do it to measure a property (what temperature does water boil at?); 
(C) I do it to observe what occurs (let's see what happens if I heat this water...).

These all seem to me to be very valid and scientific, but English doesn't seem to specifically distinguish between them. This post has turned out to be a very interesting experiment!

share|improve this question
If you are trying to find out what happens then you are experimenting. Your hypothesis is that something will happen (at the very least). There is no distinction between an interesting hypothesis and a one that implies you've done no prior research. – Matt E. Эллен Aug 11 '11 at 9:11
In short: you are not experimenting if you do not want to find something out. – Matt E. Эллен Aug 11 '11 at 9:22
I agree: but it's a question of whether the domain of what you want to find out is open (exploration) or closed (testing). – Richard Inglis Aug 11 '11 at 9:31
So you are asking a question when you already know the answer: exploratory experiment. – Matt E. Эллен Aug 11 '11 at 9:42
You might also look at en.wikipedia.org/wiki/Exploratory_research – Unreason Aug 11 '11 at 12:39
up vote 5 down vote accepted

This should be a comment, but it will run long. Here's what you note

However I'm surprised that some of the answers have implied that there's something trivial, invalid or unscientific about experimenting without a testable hypothesis: i.e. it's "just playing about" or "just demonstration".

Let me try to explain why there is a problem with a scientific experiment that has no hypothesis.

Assume you are going to do action A to 'see what happens' as a scientific experiment.

There are two possible outcomes:

a) nothing happens
b) X and Y occurred after A

Both outcomes are described incompletely (not scientifically).

In case of a), let us assume that we want to repeat the experiment. To do that, and to arrive at the same result one must know what was observed. However, once you define what you are observing (and how) you have effectively defined a hypothesis.

Similarly, in the case of b), if you do not specify if you were observing for event Z (obviously you were observing if X and Y would occur), the experiment can not be repeated (might yield different results), so the results can not be taken as scientific.

For the results of the experiment to be scientific I think you need repeatability, which must include the definition of the hypothesis and the testing method.

If none is given it is definitively not clear how were you testing (i.e. testing for anything will be different for different people). Therefore I support the opinion that you are not talking about an experiment.

However, as long as you can describe what you were doing (and it was controlled), you can extract the hypothesis that you were effectively testing and turn the experiment into formal one.

If your test was not controlled then it was an accident, as per original Bacon's definition.

You might want to read upon this article, too (do check the references though). Maybe research is better suited in this case.

share|improve this answer
+1 for Exploratory Research – Richard Inglis Aug 11 '11 at 13:10
I think Exploratory Research is the best answer, so I'm accepting your 'comment'. – Richard Inglis Aug 13 '11 at 13:36

Maybe you need to expand your understanding of hypothesis a little bit.

If you are doing something just to see what happens, then your hypothesis could be "something detectable will happen" or possibly "the resulting data will demonstrate a meaningful pattern".

share|improve this answer
Thanks, and you're right - but this isn't a helpful answer! I'm looking for a word to evoke the distinction between experiments with and without a specific hypothesis. – Richard Inglis Aug 10 '11 at 19:33
@Richard The word experiment implies that something specific and well planned is being done. I've suggested the word investigation in a different answer, but that implies a bigger more general process than just an experiment. – jimreed Aug 10 '11 at 19:58
This doesn't really answer the question. It is more of a comment. A very good comment, but not an actual response to the original question. – Ellie Kesselman Aug 11 '11 at 2:52

One rather dreary quote on a page about scientific experiments said

Any laboratory procedure you follow without a hypothesis is really not an experiment. It is just an exercise or demonstration of what is already known.

You might call an experiment without a hypothesis a scientific demonstration. The Wikipedia article explains:

A scientific demonstration is a scientific experiment carried out for the purposes of demonstrating scientific principles, rather than for hypothesis testing or knowledge gathering (although they may originally have been carried out for these purposes).

Some famous demonstrations that are mentioned are:

  • Al-Biruni's reaction time
  • Alhazen's camera obscura, lamp experiment and magnifying lens
  • Al-Jazari's crankshaft, elephant clock and programmable robots
  • Avenzoar's parasites
  • Detonating a cloud of flour
  • Foucault's pendulum

You could say one was just fooling around in the lab. For a much less serious phrase, I would look at the term (informal and may be construed as offensive) futz:

: fool around 1 —often used with around. futz around without producing any worthwhile music — John Koegel

If you wanted to describe just walking into a lab and seeing what happened, you could say:

On my day off I spent some time in the lab. I didn't have any projects, so I was just futzing around with pulleys to see what would happen.

Edit: One more serious option, as brought up by both @Richard and @Jay: scientific exploration. This brings to mind someone in a lab trying various things out in order to "see what happens". If your purpose is to be more formal, I would use this term. If you are, however, joking about playing around in a lab, I would still use "futzing".

share|improve this answer
+1 for futz, but I disagree with demonstration: that suggests an expected outcome (i.e. a hypothesis), whereas I'm thinking of an exploration where the outcome is unknown. – Richard Inglis Aug 10 '11 at 19:14
@Richard -- I think you just answered your own question -- I was about the answer "explore" or "exploration" :-) – Jay Elston Aug 10 '11 at 19:32

I know your question is about scientific hypotheses in general. But in the domain of software testing, a test case proceeds as a scientific experiment. You have a hypothesis, i.e., that under certain circumstances the software will behave in the specified manner, and you exercise the system and observe the output in order to prove or disprove that hypothesis (making the test "pass" or "fail", respectively).

But sometimes, testers execute test cases without any particular hypothesis, either for learning purposes or to refine the quality of the tests. This is called exploratory testing.

share|improve this answer
There is also the "user acceptance testing" phase to consider. I'm not sure if the hypothesis there is that the software is thought to be fully-functional and they shouldn't find any problems, or that only the really evil bugs remain (so we'll send in our top investigators to hunt them down). – FumbleFingers Aug 11 '11 at 1:14
@FumbleFingers, I'm not sure if I understand your comment correctly, but a "user acceptance test" is not necessarily exploratory in nature. See the concept of "User Acceptance Test Driven Development", in which each test (even from the user perspective) is actually a well defined script with inputs and expected outputs. And most of them produce binary, pass/fail results. – Otavio Macedo Aug 11 '11 at 1:57
I'm sure there are procedures involving the words "user" and "test" that do involve formal definitions of every aspect of the user interface and functionality being tested. But in reality those users are just testers working for the customer, not the supplier. You have to allow that not all software is so rigorously tested, and often there's at least a final phase where people just "use" the new stuff, and bugs might get found then. – FumbleFingers Aug 11 '11 at 2:07
I'm inclined to agree with Otavio. I did user-acceptance testing. It was part of the software development life cycle. I also happened to be the person who proposed the concept and proto-typed the application. But all software I've done user-acceptance testing for has been internal use only, at very large companies. And @FumbleFingers I just realized that I'm getting rather far afield for English.stackexchange! Sorry! – Ellie Kesselman Aug 11 '11 at 2:47
+1 for exploratory testing – Unreason Aug 11 '11 at 12:18

By any rational definition, an experiment without a hypothesis is an oxymoron.

There is, as @jimreed says, the "minimal" hypothesis, something interesting will happen. But quite frankly by then you've stretched the meaning of "experiment" to breaking point. Now it's just playing about.

share|improve this answer
I was going to provide the very same answer: "Playing around" or "playing about". – Ellie Kesselman Aug 11 '11 at 2:50
+1 for play, but I disagree that 'an experiment without a hypothesis is an oxymoron', see Edit2 to my question. – Richard Inglis Aug 11 '11 at 9:06

You could conduct an investigation into the behavior of a physical system. That suggests that you probably don't know everything you will try when you begin, you may not have a guess as to what you will learn, and you may follow multiple paths along the way.

share|improve this answer

You cannot conduct an experiment without a hypothesis because a hypothesis is necessary in order to know what to measure.

Lets say you just heated up some water in a closed container and at a specific temperature and pressure it became conductive or weakly magnetic. If you were not measuring temperature, pressure, conductivity and magnetism you might think that nothing had happened.

Without a hypothesis your "experiment" is certainly completely unscientific.

share|improve this answer

Very interesting question! I'm Italian and I'm asking the same question; I think that "experiment" must be intended in the broadest sense because of its importance in science. Therefore experiment is both

  • test an hypothesis (like Sir Eddington did with Einstein's relativity) and
  • make a controlled experience to get new information (just like Eratosthenes when he measured the Earth circumference; he didn't have any "hypothesis" for that)

From a quick search on Britannica online: "an operation or procedure carried out under controlled conditions in order to discover an unknown effect or law, to test or establish a hypothesis, or to illustrate a known law".

share|improve this answer

While it might still have connotations of "triviality" that you seem to wish to avoid, I cannot believe that no-one has suggested tinkering, as this is almost exactly what I would use this word to mean.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.