 One of the interesting things about money is the economists, the experts don't understand it very well at all. I used to be a volunteer at the British Museum and I used to work in the money gallery. We thought when we were setting this gallery up we'd stick a sign on the wall that said, this is money with one sentence, one paragraph explanation. Then we realised we couldn't actually explain money at all, so they just skipped that part of the gallery. Most of the money in the economy is actually just numbers in a computer system and we still think of it as cash but actually most money now is electronic. The question is, where does that money come from? And unlike the cash which is only created by governments and central banks, the money that we're actually using for most of the economy is created by commercial banks. So they create money every time somebody takes out a loan. You walk into a bank and take out a mortgage. That money isn't coming from somebody else's bank account, it's actually new money that's created effectively out of nothing through the accounting. Banks do this with a trick of double entry bookkeeping. So when you go into the bank and you take out a loan, the bank does two things. In one column of its books it enters a liability. This is the money that the bank has created and put in your account. In the other column of its books the bank enters an asset. This is the money that you owe back to the bank. Now everything is okay because the two numbers cancel out. All of the money that we're using is created as debt. For every pound that's in your bank account somebody else somewhere has a pound of debt. The entire money supply is on loan from the banking system. And what that means is we have to pay interest on all of the money that has been created. In the UK this interest adds up to 200 billion pounds a year has been transferred from the public to the financial sector. The burden of servicing this interest means that businesses and families have this obligation to keep earning money to repay all this debt. But actually the debt can never be repaid. It's a catch-22. You know as an individual you want to pay off your debts but if everyone in society did that there wouldn't be any money left because money actually is debt. So if we all pay off our debts the current economic system would collapse. What we need to do to fix the money system is remove this power to create money from the banks. Return it to some democratic, transparent, accountable body and make sure that money is created in the public interest and spent into the real economy instead of being pumped into property bubbles and financial markets. If we had a money system in which governments had sovereign control over the money supply then it would be perfectly legitimate for governments to invest in the things that we know that we need in order to create a good society a low-carbon society, a society which is sustainable, a society in which we have more equality. The money system is absolutely key to that vision. In such a system we'd still have banks but they'd only be allowed to loan money which had been deposited with them. It would reduce inflation in the economy. It would allow us to reduce resource use and it would give us a much more stable financial system. That kind of framework, an independent monetary authority with the money supply actually under sovereign control but regulated by an independent authority is a much, much safer route than anything that we had before.