The mind can handle seven pieces of information in its short-term memory and can generally deal with only four concepts or relationships at once.

人类大脑的短期记忆可以处理7条信息，而且一次可以大致处理4个概念或关系式。

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In any case, Johnson uses these four concepts to illustrate how someone can be at once in favor of a free-market society and against capitalism as its critics largely understand it.

FORBES: Charles Johnson on Free-Market Anti-Capitalism

Among the topics we discussed were the repositioning of the four Holiday Inn concepts, the impact of digital marketing and her role as a change agent for the firm.

FORBES: Holiday Inn Turns 60, Refines Brand Strategy

In just six weeks, the groups of four and five students generated 70 new game concepts which were evaluated by executives from game companies.

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