According to the phenomenalists, a material object is not a mysterious something “behind” the appearances that people experience in sensation. If it were, the material world would be unknowable; indeed, the term matter itself would be unintelligible unless it somehow could be definedAccording to the phenomenalists, a material object is not a mysterious something “behind” the appearances that people experience in sensation. If it were, the material world would be unknowable; indeed, the term matter itself would be unintelligible unless it somehow could be defined by reference to sense experiences. In speaking about a material object, then, reference must be made to a very large group or system of many different possibilities of sensation. Whether actualized or not, these possibilities continue during a certain period of time . When the object is observed, some of these possibilities are actualized, though not all of them. So long as the material object is unobserved, none of them is actualized. In this way, the phenomenalist claims, an “empirical cash value” can be given to the concept of matter by analyzing it in terms of sensations. by reference to sense experiences. In speaking about a material object, then, reference must be made to a very large group or system of many different possibilities of sensation. Whether actualized or not, these possibilities continue during a certain period of time . When the object is observed, some of these possibilities are actualized, though not all of them. So long as the material object is unobserved, none of them is actualized. In this way, the phenomenalist claims, an “empirical cash value” can be given to the concept of matter by analyzing it in terms of sensations.