In a rational world there would be no such thing as a nondiversified money market account.

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Believing one has the answer, whether or not such belief is justified, re-establishes a basic trust that we live in a just, rational-enough world.

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In a world without Social Security, the rational person would think about his own long range plans and interests.

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Mathematical theories such as Dr Nash's tend to assume a world populated by individuals who behave in fully rational ways, because they have perfect knowledge.

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Looking at those yields, a rational person would conclude the entire world must be in a Depression.

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In the real world, we rarely encounter a situation that can be completely modeled with an analytical (rational) model, so the correct answer to the model cannot purport to be the definitively correct answer to the real world situation.

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Add to this mix the change in the world of work, where, instead of a 40 hour work week in the USA and a more rational 32-35 hour work week in the much of the EU, the dot.com techies are working 60-80 hours a week, with little or no time scheduled for physical recreation or broader social, cultural, or political activities or involvement.

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