According to The Alpha Strategy, which in my opinion is one of the greatest books on investing ever in the world, there are three things one can do to preserve purchasing power: lending, investing, and buying.
There are two major problems with lending: inflation and taxation. When you lend money, the money you receive back is taxed, which eats away into any profits you could make. Another problem is that inflation eats away at purchasing power. If you keep $100 in the bank and get $103 at the end of the year in interest, inflation running at 3 per cent per year means that you are no better off by putting your money in the bank.
Lending then is only good when there is deflation. The problem with investing for deflation is that deflation tends not to happen often, mainly because government is so scared of deflation that they will do what they can to prevent it, which means that they are willing to create inflation, even though inflation hurts people by reducing the purchasing power of their wealth.
Inflation can be seen as good because inflation motivates people to work hard and spend. With the price of everything going up due to inflation, people are forced to work even harder and harder in order to afford to live. If the state is seen as an apparatus of slavery then government-induced inflation is the way that the slave owners (the government) can whip (create inflation) his slaves (the citizens) in order to get them to work.
Assuming you are able to keep your job in a deflationary recession (not a realistic assumption for most jobs) then deflation is not a bad thing because the price of goods goes down. Because deflation is not a major disaster and because it is rare, I think that it pays to not devote so much of your wealth to preparing for deflation.
Many financial advisers talk about risk tolerance and asset allocation. Asset allocation refers to the percentages you devote to certain types of investments, mainly stocks and bonds/cash, i.e. how much you will invest and how much you will lend. If you are willing to take on more risk, you invest more in stocks and if you are more of a conservative investors, you invest more in bonds/cash. In my opinion, because inflation is so much worse than deflation (because prices of things go up), then it's better to devote a little more to assets that keep up with inflation (stocks, gold, and real estate) rather than assets that do well during periods of deflation (bonds and cash).
Based on my gut-feel analysis of the world economy at the moment--during this period of "unusual uncertainty," as Bernanke described it--I believe that you should hold about 60% in stocks, 30% bonds or cash, and 10% gold.
Image: Tao Zhyn