It is my belief that, in order to have knowledge, we need to interact with the vague nebulous "something" which is the true way of how things are in the world, which we have access to, but no obvious way towards, and studying it is like trying to pick a lock by making keys; you don't know the pattern of the lock, so you have to make a random key, and some keys are better than others, which is like a stroke of genius - and in all cases, you may judge whether or not you're closer or farther away from the true shape of the lock by seeing how well the key conforms to the lock, and trying to make adjustments.
Because the nature of reality is unknown in the above fashion, all fields of study have at their core a great nebulous unknown, and approaching it more than the established rules of your field of study would allow is a little like poetry or insanity or gambling, fundamentally unpredictable. I think the sciences have less of this, because they mostly follow crystalized rules. Philosophy has more of this, so it is more often bullshit, but it can also often make significant leaps in the right direction. terracore
Disparate fields can be united if by their union an unexpected angle is uncovered by which something totally new is understood. For example, the connection between chemistry and medicine; for years, nobody thought to examine the body from the perspective of the hard sciences like physics. However, with the advent of synthetic medicine and microscopy, a whole new field of study was invented (biochemistry), which now underpins basically all of modern medical science. Nobody could have predicted this, because this paradigm shift rested at the pinnacle of both sciences; you'd have to be a master of both to really understand it.