In the last chapter, we introduced the variables of desirability, praiseworthiness, and appealingness as central variables, each of which is uniquely associated with a class of emotions, namely, Event-based emotions, Attribution emotions, and Attraction emotions, respectively. There are, however, a number of other factors that affect the intensity of emotions, and it is these that constitute the focus of this chapter. Some of these factors can influence the intensity of all three classes of emotions; these we refer to as “global variables.” Others, that we call “local variables,” have relatively local effects on emotions in particular groups. In other words, they are variables that are influential for some emotions, but not for others.
When one considers the multitude of factors that obviously can affect the intensity of emotions in one way or another, at one time or another, the total number of intensity-affecting variables that we identify might seem to be surprisingly small. In order to keep our analysis of intensity within manageable bounds, we have adopted a condition that all proposed intensity variables must satisfy. Specifically, for something to be a local or global intensity variable it must be capable of affecting intensity independently. The purpose of this requirement is to exclude from the class of intensity variables any factor that appears to have its effect only by virtue of the fact that it modulates the effect of another intensity variable.