Can you explain the problems you’ve found in the Dresden FIles’ world-building?

I said that I thought the world-building was better in Rivers of London, not that I had found particular problems.

One of the major problems with a lot of urban fantasy is how one reconciles the fantastic with the urban – how is it that magic exists but we’re still in a recognizably “realistic” urban environment environment? Is there a “masquerade” and how is it maintained? Why hasn’t magic reshaped human society and institutions, if it’s that powerful? And so on. 

(To give an example, in the latest Harry Potter movie, I had a big problem with the idea that wizards would ever be afraid of no-majs and thus hide themselves from the world, when there’s really nothing that humans could do to threaten them.)

So one of the things I like about the Rivers of London series is that Ben Aaronovitch came up with some really clever solutions to these problems. Magic hasn’t hugely reshaped human institutions because magic-users are rare, because the reliability of magic is a fairly recent phenomenon (thanks to good old Sir Isaac Newton), because the overall level of magic in the world ebbs and flows with time, because magic isn’t compatible with a lot of technology, which makes integrating it with modern society difficult, and because at the end of the day, a wizard who isn’t prepared can be taken out with conventional methods the same as any other human so they’re not all-powerful. 

Why is it rare? Because A. it takes a rather specific mindset to recognize the signs of magic in the first place (which helps with the masquerade), B. you have to be taught by a wizard, you can’t pick it up on your own (which limits the population of possible wizards), C. if you over-use magic or try to draw too much power or have a magical accident, you suffer what appears to be a stroke, brain hemorrhage, aneurysm, or heart attack (which both makes magic less enticing for new entrants, limits the power level of wizards, and explains why we haven’t noticed magic gone wrong – it just shows up as natural causes), and D. geopolitical events like the second World War led to the deaths of entire magical communities and traditions. 

How does the masquerade work? There are covert and semi-covert human institutions, largely based in the police or intelligence agencies, that work to cover up what’s going on. An outbreak of vampirism in a suburban household in London? Hit the sleeping vampires with white phosphorous grenades, have the fire marshals declare it to be a tragic electrical fire, and everything gets swept under the rug. And so on.