Nobody has ever encountered a purely chemical problem, or a strictly historical one.
Disciplines are a filing system. They exist because universities need departments, journals need scopes and careers need ladders, and they have been extraordinarily productive — depth is not achievable without some agreement about where to dig. But the divisions describe how we organise the study of the world, not how the world is organised.
Which means the boundaries are administrative, and boundaries of that kind tend to be under-patrolled.
The pattern
It repeats often enough to be worth expecting. Geology and biology were separate concerns until someone noticed the same fossils on both sides of an ocean. Statistics and agriculture produced the modern controlled experiment, because someone had to work out whether one field of barley had genuinely done better than another. Weather forecasting and computing arrived together, each unusable at scale without the other.
The common feature is not brilliance. It is position. In each case somebody was standing in a place where two bodies of knowledge could be seen at once, and noticed that a well-established answer in one was an open question in the other.
Why this favours the broadly curious
Specialists reach the frontier of their field. That is the job, it is difficult, and the frontier is where the hardest work happens. But the frontier of a single field is also densely occupied, by people who have thought about it for decades and are unlikely to have missed something obvious.
The space between two fields is different. It is not harder, exactly. It is simply that far fewer people are standing there, because standing there requires being a competent amateur twice over and enduring the specific discomfort of being the least qualified person in both rooms.
This is the closest thing modern wizardry has to a claim of usefulness. Not that broad curiosity makes anyone cleverer — it does not — but that it puts a person in an unusually productive location, and that the connections visible from there are genuinely invisible from anywhere else.
Making it a habit
The practice can be deliberate rather than accidental. Take two fields you know something about and ask, in writing, what the older one solved that the newer one is still arguing about. Ask what a luthier knows that a structural engineer needs. Ask what a stage manager could tell an epidemiologist about getting three hundred people to do the right thing at the right moment.
Most attempts produce nothing. That is the correct rate. The occasional one that works is worth an entire year of the ones that did not.