 Śrīharṣa argues that this definition of knowledge fails to satisfy the criterion of uniformity; for the relevant distinctive mark—the awareness of which is necessary for knowledge—will vary from one case to another. For example, when it comes to an awareness of a clod of earth as earth, the distinctive property X would have to be a property distinctive of earth, e.g., earthhood or having smell, etc. But when it comes to recognizing a cow as a cow, the distinctive property X would have to be something else: a property that is distinctive of cows, e.g., cowhood or having a dewlap, etc. In general, Śrīharṣa claims that there is no way of uniformly characterizing this distinctive property X that an agent needs to be aware of in order to have  knowledge.[18]