Why we call it a 'Double Thank-You Moment'

“At least half of the popular fallacies about economics come from assuming that economic activity is a zero-sum game, in which what is gained by someone is lost by someone else. But transactions would not continue unless both sides gained, whether in international trade, employment, or renting an apartment.” 

          ~ Thomas Sowell, from his 'Random Thoughts ...'

[Hat tip Thorsten Wirth] 

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