Book excerpt: Romantic love presents some of life's most challenging questions. Can we choose who to love? Is romantic love rational? Can we love more than one person at a time? And can we make ourselves fall out of love? In On Romantic Love, Berit Brogaard attempts to get to the bottom of love's many contradictions. This short book, informed by both historical and cutting edge philosophy, psychology, and neuroscience, combines a new theory of romantic love with entertaining anecdotes from real life and accessible explanations of the neuroscience underlying our wildest passions. Against the grain, Brogaard argues that love is an emotion; that it can be, at turns, both rational and irrational; and that it can be manifested in degrees. We can love one person more than another and we can love a person a little or a lot or not at all. And love isn't even always something we consciously feel. However, love -- like other emotions, both conscious and not -- is subject to rational control, and falling in or out of it can be a deliberate choice. This engaging and innovative look at a universal topic, featuring original line drawings by illustrator Gareth Southwell, illuminates the processes behind heartbreak, obsession, jealousy, attachment, and more.