There are as many reasons for falling in love as there are people and circumstances. And it is hard to know exactly what another person means by falling in love. Are they talking about intense lust? A feeling of deep connection and understanding? Pleasant company and easy familiarity? An almost spiritual experience of rapture and wonder? Preoccupation, even obsession with another person and profound fear of losing him or her? So what am I telling you? Who wrote the book of love? Well, lots of people and things did. We should never forget that we are animals and are driven by instincts to reproduce that are part of our genetic code. These instincts are profound and powerful, and even though each individual plays them out in a slightly different way, they are always at work in us. Replicate your genes! That command is sent to us by our hormones, our emotions, our families, our society, our deepest selves.