There was once an accounting firm where the senior CPA knew everything there was to know about accounting. He could answer any question. He knew all the tax laws: There wasn't a better accountant anywhere.

Every morning when he came to work, he would unlock his desk drawer, open it up and look inside for a moment, and then close and lock it again.

This puzzled all of his co-workers, because it was the only eccentricity that this genius exhibited. For years no one dared to breach etiquette and snoop through his desk, but his odd behavior became something of a legend around the office.

One day when the elderly man was home sick, one junior accountant could control himself no longer. Taking a letter opener he carefully pried open the desk lock.

Inside he found one sheet of paper, and written in large letters was:

"DEBITS ON THE LEFT...CREDITS ON THE RIGHT"