 Whether folk emotion categories are homogeneous enough to qualify as theoretical kinds has important methodological implications. To the extent that they are, the prescriptive definitions of emotions the theorist offers can achieve both theoretical fruitfulness and maximal compatibility with ordinary linguistic usage (in such case, prescriptive definitions will also be descriptively adequate). To the extent that they are not homogeneous enough, prescriptive definitions will have to explicate folk emotion categories, transforming them so as to increase theoretical fruitfulness while giving up on some degree of ordinary language compatibility (Carnap 1950). 