We have reached a level of institutional complexity which renders radical simplification impossible, short of outright collapse. We can see this even in relatively simple structures like that of U.S. financial regulators: such things are much easier to create than to abolish, and so they tend to multiply. But it’s even more true of finance more generally. The world’s biggest banks must become much simpler; the world’s biggest banks won’t become much simpler. The conclusion is not a pretty one.