Here is a recap of the main points of post-keynesianism. I'm going to try and keep it short, so you will not find arguments, justifications, or retorts to standard questions. Just the core tenants as I see them.1. Federal Deficit Spending Funds Private Savings
In a fiat money system, the State is a currency issuer, while all other parties (including foreign entities) are currency users. Just as in a basketball game, where each team competes hard for points which are meaningless to the score keeper, the State does not need or value money as it can create as much as it chooses at will. To a fiat currency issuing State, money is just points, to be manipulated to maximize real output.
Therefore the State does not need to tax in order to spend. In fact, when the State taxes it destroys money. Similarly, when the State spends, it creates money. When the State spends more than it taxes (runs a deficit) then it is net injecting newly created money into the private sector. When the State runs a surplus, it is draining the private sector of money. The net quantity of money that the State injects into the private sector sloshes around in there as savings, or more accurately, net financial assets. This mechanism is the only way that the private sector can enjoy positive net financial assets, as the liability exists in the Government sector.
I like to think of Federal Debt as "paid in equity" as it is the net financial assets that the State creates and transfers to the private sector for that sector to then leverage on top of.
The purpose of taxes, then, are not to fund Government spending. They are to 1) create demand for the currency in the first place and 2) regulate aggregate demand. If aggregate demand gets too high and creates inflation, the State can raise taxes, run smaller deficits, and drain the private sector of money. The private sector will then have less money available to spend on stuff, and this will tame inflation. In periods of insufficient aggregate demand (like now) the State should lower taxes to fund private sector savings, and reduce deflation.2. Loans create deposits
Within the private sector, there are entities known as "banks" which are public private partnerships designed to extend prudent credit (make loans that get paid back). Their function has been incredibly perverted in recent years, but nevertheless this is their purpose and it is why they are given access to "reserve accounts" at the Fed.
When a bank makes a loan it does not drawn down a deposit. It simply creates the loan and credit a receivable asset. This then creates credits a deposit liability at some other bank in the system. If these two banks are the same, then nothing further happens -- the loan has created a deposit. If the two banks are different then the bank making the loan debits its reserve account, and the bank receiving the deposit credits its reserve account. The bank short reserves can either try to attract some deposits back, or it can borrow what it needs on the overnight interbank lending market, or, if the system is short reserves as a whole, it can borrow at the discount window directly from the Fed.
The Fed manages the total level of reserves in the system by issuing Treasuries. Treasuries drain reserves, and thus create a situation where some banks are short reserves, and others are long (instead of a situation where every bank has more reserves than it needs). This creates the overnight interbank lending market as firms trade to hit their reserve targets.
Note that banks are not reserve constrained in their lending in any way. Bank lending is constrained by capital requirements on the supply side, and creditworthy customers on the demand side. In essence, banks have license to "print money" and do so by expanding both sides of their balance sheet at the same time when making a loan. Private capital is in first loss position to encourage banks to only make loans that should be paid back, but a host of innovations (such as securitization) has dramatically undermined the banking sectors ability or interest in assessing credit accurately.
All bank spending, in fact, is done through balance sheet expansion, as they print money to pay salaries, buy printers, and eat lunch. I know, this is crazy, but it's true. Conversely, when loans get paid back (or are written down), money is destroyed and balance sheets contract.
Also note that Treasuries are simply a mechanism to drain excess reserves, and thus create an interbank overnight lending market, and thus set the Federal Funds rate. Treasuries are not the US Govt "borrowing" money and they could stop doing so at any time to no ill effect. In today's ZIRP environment, there wouldn't be any discernible effect at all, actually.Lay off the Chinese
China buys a lot of US Treasuries, but China is not "funding" the US in any way. Rather, the US is funding China's desire to save US$. China makes real stuff, and gives that to the US in exchange for $. These $ live in a reserve account. When the US issues Treasuries, some of these $ move from reserve accounts to Treasury accounts. When they mature they will move back to reserve accounts. It is no big deal.
I think that's about it. All of the above is based on accounting and operational reality. It is not a "theory" -- merely a description of how things work in actuality. It decimates all of Macroeconomics and the Federal Governments policy towards debt, finance, the financial industry, and unemployment.