During the final year of my Zoology degree I was lucky enough to do my dissertation at Edinburgh zoo, studying communication between collared peccaries. At the time Edinburgh zoo was the only zoo that actually went into the enclosure with the peccaries. It turns out that the staff at the zoo aren't particularly keen on the students, seeing them as know-it-alls with no practical experience. Before I went into the enclosure I was made aware, by the keeper, that my classroom learning was worthless inside the enclosure and that I was to do exactly as I was told if I wanted to keep my access to the animals.
As our relationship thawed I found the keeper to be an absolute fountain of knowledge about the peccaries, their habits, quirks and behaviour. I found that my time working with the animals (I helped clean the enclosure, feed and tag them and help the vet when required) was where I really started to learn about behaviour. My classroom learning hadn't been a waste, it was just one part of a greater whole. It gave me a frame of reference from which to understand what I was seeing.
At that time I was heavily into the martial arts and I couldn't help but draw parallels. The drills and training sessions were an important frame of reference for me to draw on. They gave me a set of theoretical tools which I had to turn into a skillset or style that worked for me practically. I did that through trying these things in a practical setting (sparring, competition fighting and door work). This is almost always a one way process - if something doesn't work for you practically, then you adjust your frame of reference. The martial arts is a very good way of learning this one way rule. The consequences of trying to force your theoretical knowledge on to unwilling reality are usually immediately apparent (she can be a harsh mistress).
The point I am working towards here is that this is true of any endeavor. It really doesn't matter how beautiful your theory is, or how much it should work, if it doesn't match reality then it's wrong. Results (in a practical setting) or observations (in a scientific setting) always trump theory. Unfortunately it is really easy to fall in love with a theory and it's even easier to twist your view of reality to accommodate "glitches". However, I don't think there is a worse way to lose an argument than to have to run off with your tail between your legs when someone simply says "don't tell me you are right, show me".
As a quote on this subject, I particularly like this from an animal trainer Gary Wilkes:
Good science does not propose rules that are not confirmed by an objective observation of nature. Good science reveals nature as it is. If reality contradicts science, then it’s not really science.
