When you hear who said, "If music be the food of love, play on," you will probably not be too surprised or shocked!
"If music be the food of love, play on,Give me excess of it; that surfeiting,The appetite may sicken, and so die."
This comes from Act One, Scene One, lines one through three from the play Twelfth Night.
Most of us know that Shakespeare coined a great deal of quotations that are in common usage today. We would not really say that "If music be the food of love, play on" is in common use, or at least not as common use as some of Shakespeare's other sayings. However, we should still investigate what these words means. Perhaps they will help you to better understand some of Shakespeare's other sayings.
The words here are not too complicated too unpack. The speaker is acknowledging that music seems to be the "food of love," or that music makes the individual inspired to love. Perhaps the person even feels that music causes others to fall in love with him or her. In the context of the words, we see that the speaker desperately wants love. By being "fed" love, the appetite will eventually go away. He feels that he needs love to survive.
Page through some of Shakespeare's other works. You will quickly find that he frequently uses images of food to demonstrate love and a whole field of other emotions and ideas.