As I commented on that blog post, Keynes didn't think preventing booms was the right answer. From The General Theory of Employment, Interest, and Money, Chapter 21 - Trade Cycle - Section III:
Thus the remedy for the boom is not a higher rate of interest but a lower rate of interest! For that may enable the so-called boom to last. The right remedy for the trade cycle is not to be found in abolishing booms and thus keeping us permanently in a semi-slump; but in abolishing slumps and thus keeping us permanently in a quasi-boom.Read all of Chap 21, Section III, for the complete reasoning. Instead of preventing bubbles Keynes thought the key to managing the business cycle was to redistribute income to people who would spend it on consumption:
"Furthermore, even if we were to suppose that contemporary booms are apt to be associated with a momentary condition of full investment or over-investment in the strict sense, it would still be absurd to regard a higher rate of interest as the appropriate remedy. For in this event the case of those who attribute the disease to under-consumption would be wholly established. The remedy would lie in various measures designed to increase the propensity to consume by the redistribution of incomes or otherwise; so that a given level of employment would require a smaller volume of current investment to support it."From The General Theory of Employment, Interest, and Money: Chapter 21 - Trade Cycle - Section III. In other words, the problem with a boom is that eventually over-investment results in over-supply of the popular assets at which point investors reduce investment spending, which reduces overall demand, which triggers a recession. However, the recession can be avoided if we shift income to consumers when the investors start reducing their investment spending so that overall demand (investment + consumption) doesn't fall.
Reading these arguments from Keynes reminded me of a recent post by Robert Reich who argued that no amount of monetary or fiscal stimulus would fix the recession because the problem is that the middle class has run out of ways to increase their consumption spending:
Ultimately, even if fiscal and monetary policy weren’t deadlocked, we’d still face the same conundrum. Say the White House and Ben Bernanke got everything they wanted to boost the economy. At some point these boosts would have to end. The economy would have to be able to run on its own.This in turn got me thinking: what if the current recession was a natural and inevitable consequence of the upward redistribution of income America has seen over the last few decades? If the middle class spends every extra dollar of income it receives, but the upper class saves most of every extra dollar it receives, then having most of GDP growth go to the upper classes will result in savings and investment steadily growing while consumer demand grows at a slower rate. Eventually this will result in a situation where the upper classes have fully invested in every existing profitable investment opportunity available at that level of consumer demand and there are few new opportunities for profitable investment because underlying consumer demand is not growing fast enough. At this point the upper classes will cut back their investment spending, triggering a recession unless some other sector (government, consumers, or exports) increases its spending by an equal amount.
But it can’t run on its own because consumers have reached the end of their ropes.
After three decades of flat wages during which almost all the gains of growth have gone to the very top, the middle class no longer has the buying power to keep the economy going. It can’t send more spouses into paid work, can’t work more hours, can’t borrow any more. All the coping mechanisms are exhausted.
Anyone who thinks China will get us out of this fix and make up for the shortfall in demand is blind to reality.
So what’s the answer? Reorganizing the economy to make sure the vast middle class has a larger share of its benefits. Remaking the basic bargain linking pay to per-capita productivity.
You can look at the recent housing boom and bust through this paradigm. As the point of exhaustion of profitable opportunities was reached the financial system started shifting more and more of the excess savings of the upper classes to the middle class through mortgages that were easier and easier to obtain (read sub-prime). This resulted in growing middle class demand for housing which in turn resulted in full employment through growing construction employment. The problem was that because the excess savings were shifted to the middle classes through the mechanism of loans the process could not continue indefinitely. When the middle class could no longer afford to increase their debt service the flow of money from the upper classes to the middle classes abruptly stopped and the recession started.
How to avoid this cycle? It seems to me that the key for steady economic growth is to ensure that every dollar of GDP growth gets more or less distributed evenly on a per capita basis, i.e. if GDP grows by $100 the top 10% income bracket should receive only $10, and the bottom 90% should receive $90. This way consumer demand will steadily grow as GDP grows and the reduced income of the upper brackets will mean that there is a healthy shortage of capital for investment so that every additional dollar of upper bracket income will get spent on profitable investments.
But how to do this? One obvious way would be to make taxes more progressive (raise taxes on the upper brackets and reduce taxes on the middle class) so that middle class disposable incomes and upper class disposable incomes grow at equal rates. Another way would be raise taxes on the upper brackets and increase government spending. Or we could keep taxes low and have the government borrow the excess savings of the upper brackets and then use deficit spending to support demand. Or we could devalue the dollar to make our industries competitive in the global market and increase demand for exports. Of course it is easy to find flaws with each of these approaches, but doing nothing will result in a perpetually stagnant economy.