In all logics that fail to make this connection and distinction between logical and non-logical operations there is no criterion for data. If ultimate simplicity is demanded of the data, there is no standard for simplicity except the _minimum sensibile_ or the _minimum intelligibile_ which have recently been resurrected. On the other hand, where simplicity is waived, as in the logic of objective idealism, there is still no criterion of logical adequacy. But if we understand by _logical_ data not anything that happens to be given, but something _sought_ as material for an hypothesis, i.e., a proposed solution (proposition) of an ambiguous object of conduct and affection, then whatever results of observation meet this requirement are logical data. And whenever data are found from which an hypothesis is constructed that succeeds in abolishing the ambiguity, they are simple, adequate, and true data. No scientist, not even the mathematician, in the specific investigations of his field, seeks for ultimate and irreducible data at large. And if he found them he could not use them. It is only in his metaphysical personality that he longs for such data. The data which the scientist in any specific inquiry seeks are the data which suggest a solution of the question in which the investigation starts. When these data are found they are the "irreducibles" of that problem. But they are relative to the question and answer of the investigation. Their simplicity consists in the fact that they are the data from which a conclusion can be made. The term "simple data" is tautologous. That one is in need of data more "simple" means that one is in need of new data from which an hypothesis can be formed.