Neuroeconomists use devices, like MRIs, to observe the behavior of real people buying and selling things.

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The public is sitting in passive index ETFs now, no need to trade or to have a broker or mutual fund manager buying and selling things on their behalf.

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The superwealthy will do fine buying and selling things.

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Those that buy and sell equities or bonds do little more than estate agents, selling and buying things about which, for the most part, they have little understanding and they are about as considerate to their customers.

ECONOMIST: Financial services