ABSTRACT
In bringing out the character and the epistemological importance of this “family” of related sense-data, the phenomenalists have performed a valuable service to philosophy. The epistemological analysis, which separates out the sensory qualities of various kinds of sense-data, examining them in and for themselves, is an indispensable mental function. The category of causality is then given, not as an order among sense-data, but as a relation between the self and those active things with which it is in contact. The character of the sense-datum is dependent on many factors besides the table; some of them, which are causes of variation, are called light, and eyesight. The constant factor which is responsible for the similarity in the series is called the table; and its place in space is the place at which the set of sense-data can be obtained. Materialism derives some of its attractiveness from the apparently solid and vivid reality of material things.
