[overboard2]

You don't need a preexisting theory though, you just need to lack one that explains the results of an experiment

[tdehnel]

Why would someone do an experiment without a theory to test? How would they know that a particular result was interesting without a theory about the expected result?

[foodjinn]

Because rubbing your chin doesn't accomplish anything, messing around with stuff does.

[tdehnel]

There are practically infinite combinations of things to mess around with. Which stuff do scientists choose to mess around with and why?