by Paul McCartney Now I know that it can easily happen To someone like me I don't want to step on anybody's toes Who knows how to find love Think before you give your answer Who knows what a mystery may bring Once in a life I'm a lucky man If I can find the kind of love That's gonna last for me Twice in a lifetime Is one of those unspoken dreams We usually reserve for fantasy Who knows how we find love Stop before you give your answer Who knows when a mystery begins I know, I know I know because it's happening to me I know, I know Twice in a lifetime Is one of those unspoken dreams We usually reserve for fantasy Who knows how we find love Stop before you give your answer Who knows when a mystery begins I know, I know I know because it's happening to me