When he wrote these words for Polonius in Hamlet, William Shakespeare probably didn’t expect them to be regurgitated centuries later. Originally, the quote was taken to mean that one should never borrow money because it leads to the destruction of a friendship. But there weren’t any banks around in the 16th century. Now, it makes sense to borrow money for big purchases – like a house – and pay it back. Or having a 0% credit card to cover surprise bills (just make sure you pay it off ASAP).