Please send your questions for publication to prudence@slate.com.

Dear Prudence,

Help! I'm torn and would love to hear your take on my dilemma. I received a sweater from a sibling for the holidays but decided to return it because it didn't fit. I looked around the store (a major national retailer) for a possible exchange but came up empty-handed, so I simply asked for a refund. Today, I received a check for about $550 more than the amount in question. Because I could definitely use the cash, my first thought was to rush out and deposit it before the store recognized its error. But I know the money isn't really mine. Now I'm faced with the choice of benefiting from someone else's mistake or returning a tidy little windfall that would certainly come in handy. Some friends have urged me to take the money and run, others have suggested I take the high road by writing the company to explain what happened and hope that maybe my honesty would be rewarded with a gift certificate or a similar show of gratitude. Prudence, what would you do in my situation?

—Tempted

Dear Tempt,

It is a temptation because it's easy to think, well, it's a big company, it won't matter, nobody will know. But alas, you will know, and Prudie thinks you had made your decision even before you wrote. Anybody who grapples with this problem is obviously inclined toward doing the right thing. As for "a show of gratitude," do not get your hopes up, cupcake. "Major national retailers" are not individuals to whom you return negotiable bonds found in the back seat of a taxicab.

—Prudie, affirmingly

Dear Prudence,

FYI, and for "Cramped," stores such as Crate & Barrel and Filenes will actually give you cash (or a check, actually) for returned wedding presents. So if "Cramped" really wants cash instead of gifts but doesn't want to appear so tacky as to provide a direct deposit account number with her invitations, I would suggest that she register for food processors and the like at C&B. (I know this only because we did get two food processors for our wedding this year, and were pleasantly surprised at the availability of the cash refund.)

—Dennis