A lot of what people will claim as economic problems are not, in fact, economic problems.
They are, rather, attempts to get the rest of us to do what the people doing the claiming want us to do.
On the other hand, some things that people don't pay much attention to actually are economic problems.
Which we need to take note of and even do something about.
People are taking their money out of the weaker banks and, instead of putting it back into stronger ones, are keeping it as cash.
As Arief Hossein Khan, of Bangladesh Bank, says, this “is not positive”.
This is, in fact, the same problem that afflicted the American economy in the 1930s, what everyone was worried might happen in 2008, that Great Financial Crisis.
That the GFC did not become another Depression was because action was taken to make sure it did not.
Now, yes, the Bangladeshi situation today is on a much smaller scale but it is indeed something that is concerning.
There's something called the money equation: MV=PQ. Money, times velocity, equals prices times quantities.
Or, much simpler, the amount of money we have times the number of times we use money equals the prices of things we use money for times the quantity of things we use money for.
It's an identity, simply a statement of obvious truth.
Among economists, this is universally agreed to be true. Where the arguments start is how useful this is.
Milton Friedman was one who thought this to be very useful and very important. His argument about the cause of the Depression in America was based upon this.
The banks start to go bankrupt. This means that V, that velocity, starts to fall. For what makes the money go around is us putting our money into the banks and the banks then lending it out again.
So, if the banks aren't there any more, then we have the same amount of cash money from the central bank -- notes and coins and so on -- but that MV falls.
This then means that prices, or the quantity of production, must fall -- a depression where we have falling GDP and also deflation in the worst outcome.
The general agreement is that no one really enjoyed that Depression of the 1930s. So, when the banks started to fail in 2008, something was done.
This was quantitative easing, the printing of lots and lots and lots more money because velocity was falling. We didn't all enjoy 2009/10, that's true, but we didn't have a depression, which was good.
You'll be able to find all sorts of economists who say that there are other problems, other solutions even. But this basic idea -- do not allow the money supply, that MV, to fall too much -- will be agreed upon by nearly all.
So, some of the Bangladeshi banks are not doing too well. We're taking money out and keeping it in cash. That means that V is falling -- because we're not putting it back into other banks that then lend it out again.
Again, yes, this is not happening in some great wave, it's a small thing. But it is something that could become a problem and so it's something that we should do something about.
The answer is as before -- the Bangladesh Bank should print more money.
Which, in fact, it is -- that's the effect of the lending the central bank is doing to banks at present. The “liquidity support” as it is called.
So this isn't something that we have to worry about a lot. But it is a useful example of how human knowledge advances.
A century ago, we didn't know this and the US had their Depression. Now we know about this -- do not allow the money supply to contract -- and so know what to do about it.
We've also the very comforting thought that the Bangladeshi central bank knows about this and is doing something about it.
Tim Worstall is senior fellow at the Adam Smith Institute in London.