We found his story unusual, even charming considering how many years had passed and how low the duty would have been. But little did we know that where personal importations are concerned, guilty consciences can nag and prod their owners more often, and for far longer, than one might think.

Consider the following, submitted by Larry Thorns, Entry Branch supervisor at the Dallas/Ft. Worth Airport:

About the time U.S. Customs Today was reporting on one guilty conscience, another was sending the DFW port of entry four hundred dollars in overdue duty. And that's the only way the sender can be identified: another guilty conscience.

The DFW port of entry received an envelope with a local postmark but no return address. Inside was an unsigned note that confessed, "Many years ago I bought a string of ... coral beads. I failed to declare them and it has been on my mind. I am not a dishonest person so I want to pay what I think the duty would be." Enclosed were two money orders, one for $300 and one for $100.

The person had signed the money orders, but the signature was virtually illegible.

Upon receiving the letter, a Customs inspector filled out Customs form 368 (Collection Receipt or Informal Entry), duly noting the entire transaction: He entered the numbers on the money orders; the verbal description and number code of the merchandise declared; and for the importer's name, address, and phone number, he wrote "unknown."

Writers and philosophers have weighed in over the centuries with lofty pronouncements about conscience and its role in human behavior.

Here are three observations:

The Canadian poet Irving Layton said that conscience is self-esteem with a halo; the French author Victor Hugo said that conscience is God present in man; the American publisher and author H.L. Mencken called conscience a mother-in-law whose visit never ends.