★ Dirty Harry and Opportunity Cost

"Let’s say Inspector Callahan wanted to buy a .44 Magnum for $500. Harry’s opportunity cost of buying the gun includes everything he could have done with that $500 if he didn’t buy the gun in the first place. For example, he may have been able to invest that money and earn a rate of return of 6% over a 12 year period. In that case, his opportunity cost would be equivalent to $1,000 in his pocket 12 years from now."