[In fact, I once took an economics course at Dartmouth and the professor informed me that supply-demand theory is basically BS, a myth, an attempt to explain raising prices for the masses...prices are determined by what you can get away with? ]
Obviously, he was a BS keynesian.
Prices are always what you can get away with. The consideration is, if your price is above the market clearing price demand will fall and supply will increase as you fail to sell your product. Likewise, if your price is below the market clearing price, demand will increase and the supply will decrease leaving you empty handed. or the shelves empty. Price is a discovery process and after it is settled on, it tends to stick for a time, until either supply or demand changes. That is why tomatoes cost more in the winter time.
The increase in the money supply is what makes prices go up. Our government thinks printing money helps the economy. If a good fairy came in the middle of the night and doubled everyones money, nothing would change. Very quickly everything would cost twice as much as before. The next day the demand for products would double therefore the prices would double to maintain the supply, else the shelves would go bare.
TM here is an excellent little book explaining many of the things that we have come to believe that are simply not true. I wish everyone would read it. It was helpful to me.
http://mises.org/store/Unmasking-the-Sacred-Lies-P569.aspx