anywhere is an equation. does the fisherman catches his fishes without a technique? does a hunter hunts a bird with bare hands, a lion with a bow, and a boar with a gun? no, they always have "equation" for any case. the world was made respecting logic. if you pour water into a glass it will stay there in all the cases never float away. the emotion is just an answer to something logical, you do something to get an emotion. even more, when affected by emotion, the body behaves itself in a fixed number of ways. from these the body choose one or more ways to behave in proportion with the degree of emotion/intensity of stimulus.