The lecturer at the school of optometry was asked by a student how did he figure pricing for his patients.

He replied, "That's easy. You start by saying, 'That will be one hundred dollars,' and watch the patient as you say it. 

If he doesn't flinch too badly you continue... 'for the exam. The glasses will be another hundred.'

Here you make another slight pause, and if there is still no sign of terror, you quickly add... 'for the frames, the lenses will be another hundred,' and here ever so slight a pause for reaction before you finish . . .

. . . 'each.' "