I think the only reason one loves, monsieur, is for his own pleasure. JEAN ANOUILH. Cecile (1949) tr. Luce and Arthur Klein.
Living beings develop affection for others because of a unique chemical reaction in their bodies. Love is a chemical reaction, like the brewing beer stalk, which charges up certain chemicals, endorphins, inside your body to make you feel good. Goose bumps, sinking and choking of heart, dry mouth, lost speech, blushing cheeks, tremor in legs are all responses induced chemically.
Feeling good is an individual response determined by cultural, social and environmental factors. Setting aside the Aristotelian argument of what should make you feel good versus what does make you feel good, we can begin our discussion with the observation that if it did make you feel good, you will want more of it. It is similar to the addiction of an opium junky, except now your own body manufactures opium. The law enforcement authorities keeping you from abusing these illicit drugs here are not the police but the religious, social and cultural customs.
We continually exude, through the billions of pores of our skin and through our breath, the volatile chemicals, the pheromones. These unique chemicals enter the bodies of those around us without them realizing of this chemical courtship. Insects influence each other's behavior by generating odorous substances, which signal sexual interest, danger, and such. Though such chemicals have not been isolated for humans, evidence is strong that they do exist and why shouldn't they? We are all too familiar with the power of odors. From the ritual use of incenses in Buddhist shrines to the aromatic cocktails on Champ de Ellyses, we know what odors can do. You can tell if you have been infected by pheromones; infatuation, crush and love at first sight can only be explained through chemical equations.
Pheromones invoke a chemical reaction that stirs a pleasant response. With each exposure you become more dependent on this "feeling good" response. Even when it is love at first sight, pheromones invoke positive responses. When the dependence becomes strong, we begin to experience withdrawal symptoms, we call ourselves having fallen in love. Saying you cannot live without someone starts to make sense, like an alcoholic cannot live without his bottle. Missing someone not around is a mild form of withdrawal. Some say love endures; and endure it does for only as long as these chemical reactions continue. Loved ones living apart for longer time lose their affection, just like an opium junky without his shot in the arm for a long time can get cured of his addiction. Even when chemical courtship continues, people often become refractory to these chemicals and we call it losing charm; monotony of a response makes it less pleasurable and the human brain begins to search for greater delights.
It all begins with the dancing of chemicals in the air. It is the chemicals in the air that create the close bonding between a child and mother, it is the chemicals in the air that make a man run away with another woman and it is the chemicals in the air that force a woman to kill her husband for infidelity. And it is the chemicals in the air that make new brides blush when saying, "I do." Chemicals, chemicals on the wall, who is the most infatuating of all.