Abstract
The categories we create and how we think about these categories are fundamentally important—and are often open to misinterpretation. The following points are illustrated using examples related to gender, sexual orientation, and other aspects of sexuality: (a) Categories are created by people; thus, there are no objective or universal definitions. Definitions change over time and place, and they have political implications, advantaging some people and disadvantaging others. (b) Beware of exaggerating differences between categories. A significant difference between groups does not mean that they do not overlap; they usually overlap considerably. There is almost always more variability within groups than between groups. (c) Categories are often proxies for other variables. When interpreting differences between categories, remember that other variables confounded with these categories could be driving the effect. (d) Neither a similarities perspective, in which the differences between two categories are minimized or ignored, nor a differences perspective, in which the differences between the two categories are emphasized or exaggerated, has totally positive or negative consequences. It is often useful to consider both.