Economics, Investment, Inflation, and Debt

My brother and I were talking the other night and I had an insight (being only informally trained in economics - I could have been taught it if I'd just taken a class). But I don't know if there's a name for it. So I'm asking.

I heard an ad for investing in gold. The price per ounce has gone up a lot in the past couple years, and is understandably predicted to continue to rise. Right now I think the commercial said the going price is $700 an ounce. But while I might have $700 free cash to invest waiting for the gold to increase in value, I'm not allowed to buy gold one ounce at a time. So there is a minumum amount of money I have to have before I can participate in investment. Buying a home is very similar. Debt makes money more available in larger amounts (paid back in smaller increments), thus raising the minimum line.

Bartering went out of fashion because having one cow didn't work as a trade for one spear, since the cow was really worth say, 300 spears. So we have capital, money, to be the fluid in between and prevent us needing a minimum number of available cows to trade in order to participate. Capitalism, therefore, should have fixed the minimum line problem.

But then we add inflation (caused by debt on a national level), which depriciates the money someone below the minimum line has, so that they are, rather than gaining worth by saving money, actually losing ground. They must continue going to work (as an employee, most often) just to get enough money to survive - if that. And there's no way out. This is the modern equivalent to serfs, or the slave class.

Marx saw this, I assume (never read Marx myself), but his solution doesn't solve anything. It emphasizes inflation and simultaneously erases any home of overcoming it through investment. Marxism is like bailing water from a still-sinking boat.

So what's it called, the minimum line to participate in investment that would protect your income?

And what should we do?

To God be all glory.