Or an quote from Ayn Rand might answer the question much more concisely.
"Do you wish to know whether that day is coming? Watch money. Money is the barometer of a society's virtue. When you see that trading is done, not by consent, but by compulsion--when you see that in order to produce, you need to obtain permission from men who produce nothing--when you see that money is flowing to those who deal, not in goods, but in favors--when you see that men get richer by graft and by pull than by work, and your laws don't protect you against them, but protect them against you--when you see corruption being rewarded and honesty becoming a self-sacrifice--you may know that your society is doomed."
"Trading on margin is a good deal like paddling around the edge of the old swimming holeâit seems safe and easy at first, but before a fellow knows it he has stepped off the edge into deep water. The wheat pit is only thirty feet across, but it reaches clear down to Hell. And trading on margin means trading on the ragged edge of nothing. When a man buys, heâs buying something that the other fellow hasnât got. When a man sells, heâs selling something that he hasnât got. "
From Letters from a Self-Made Merchant to His Son by George Horace Lorimer
"Do you wish to know whether that day is coming? Watch money. Money is the barometer of a society's virtue. When you see that trading is done, not by consent, but by compulsion--when you see that in order to produce, you need to obtain permission from men who produce nothing--when you see that money is flowing to those who deal, not in goods, but in favors--when you see that men get richer by graft and by pull than by work, and your laws don't protect you against them, but protect them against you--when you see corruption being rewarded and honesty becoming a self-sacrifice--you may know that your society is doomed."
Quote from Roark:
The same concern arises with stocks and commodities. How do you know the keeper actually has the shares that they're selling? Selling shares you don't own and haven't borrowed is called naked shorting.
"Trading on margin is a good deal like paddling around the edge of the old swimming holeâit seems safe and easy at first, but before a fellow knows it he has stepped off the edge into deep water. The wheat pit is only thirty feet across, but it reaches clear down to Hell. And trading on margin means trading on the ragged edge of nothing. When a man buys, heâs buying something that the other fellow hasnât got. When a man sells, heâs selling something that he hasnât got. "
From Letters from a Self-Made Merchant to His Son by George Horace Lorimer
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