Life is full of unanswerable questions. Some are profound and some are silly. To quote the Mock Turtle from Alice In Wonderland: "No wise fish would go anywhere without a porpoise." Well, in this song we learn that "Everything happens for a raisin." Of course, that doesn't necessarily guarantee that the raisin is a good raisin or that the reason is a good reason, for that matter. As for the last line of the song which states, "Why ask why when you could ask what for?" The point there is that whereas asking why is just an inquiry to discover a general reason, asking "What for?" is more focused on a purpose, or should I say, a porpoise.