A doctor notices a sidewalk stand that says
'brains for sale.'

He goes over to investigate and sees a sign that says
'Doctor brains $8.00 a pound"
and another sign that says
"saramedic brains $12.00 a pound, Nurses brains $30.00 a pound, truck driver $40.00 a pound and lawyers brains $90.00 a pound."

So he asks the man behind the cashregister,
"how come his brains are only worth 8.00 and a lawyer's worth 90.00?"

The man replies,
"Do you know how many lawyers it takes to make a pound of brains?"