The Ascent of Money is filled with great citations to the academic literature. Don't have my copy handy, but you should check it out if you're interested in more info about fractional reserves.
You should also read up on "natural experiments." They got us things like the elimination of cholera from major metropolitan areas, the link between smoking and heart disease, and Hubble's Law describing the expansion of the universe. Sometimes looking at the world tells us stuff about the world.
You should also maybe check out the work of John Ioannidis, and the hoax research of John Bohannon, and articles on publication bias. Check out how frequently lab p-values cluster just around publishable.
We've reached a weird state where, give me a natural experiment in economics, where the author actually has to think about and discount possible alternative explanations sufficiently to sway aggressive critics on a contentious topic. Then give me a modern nutrition study claiming that some fad food abruptly cures cancer in rats, with a convenient p of exactly 0.05, which becomes an isolated media frenzy before it's never cited again. I'm going to treat the economics with far more deference, despite my general fondness for double-blind RCT.
EDIT: Also, the original reference was a simile, signaled by words like "essentially" and "like." Ease up a bit with the 'toy words' accusations, I was not trying to claim economics is literally indistinguishable from physics, just that the case studies here are surprisingly compelling, and seem to point in one clear direction.