Helen Fisher one of the lading experts of the romantic love and anthropologist has renewed her collection with "Why Him? Why her?" which tells you whether you are attracted to a person in your first meet or not, whether you admit the law of attraction or not.
The expert says that if you are single you're intrigued; if you are happily involved with someone then you are careful. She also adds that the compatibly depends upon the status, the life conditions and the personality has to match with each other. After lots of research with the literature Fisher says that there are 4 types of chemicals that play the leading role in who we are, the two type of sex hormones, testosterone and estrogen, neurotransmitters, dopamine and serotonin.
She says everything is chemical and everything is physical. You have to know every single thing in your life is chemical and then you have to enjoy the feel of it as well. Dr Fisher says "To me, understanding the system expands my wonder. In the wild, all animals are attracted to some other animals and really uninterested in or repelled by others - too old, too young, too scruffy. With the evolution of humanity, it became more refined and more profound and led to a phenomenon we call romantic love."