In the next place, how do we reach a knowledge of the _specific natures_ of substances?(233) What is the character, and what are the limitations, of such knowledge? Here, especially, the very cautious and moderate doctrine of scholasticism has been largely misconceived and misrepresented by phenomenists and others. About the specific nature of substances we know just precisely what their accidents reveal to us—that and no more. We have no intuitive insight into their natures; all our knowledge here is abstractive and discursive. As are their properties—their activities, energies, qualities, and all their accidents—so is their nature. We know of the latter just what we can infer from the former. _Operari sequitur esse_; we have no other key than this to knowledge of their specific natures. We have experience of them only through their properties, their behaviour, their activities; analysis of this experience, _a posteriori_ reasoning from it, inductive generalization based upon it: such are the only channels we possess, the only means at our disposal, for reaching a knowledge of their natures. 63. PHENOMENIST DIFFICULTIES AGAINST THIS VIEW. ITS VINDICATION.—Now the phenomenist will really grant all this. His only objection will be that such knowledge of substance is really no knowledge at all; or that, such as it is, it is useless. But surely the knowledge that this mode of being _really exists_, that there _is_ a mode of being which “exists in itself,” is already some knowledge, and genuine knowledge, of substance? No doubt, the information contained in this very indeterminate and generic concept is imperfect; but then it is only a starting point, an all-important starting point, however; for not only is it perfectible but every item of knowledge we gather from experience perfects it, whereas without it the intellect is paralysed in its attempt to interpret experience: indeed so indispensable is this concept of substance to the human mind that, as we have seen, no philosopher has ever been really able to dispense with it. When phenomenists say that what _we_ call mind is only a bundle of perceptions and ideas; when they speak of the flow of events, which is _ourselves_, of which _we_ are conscious,(234) the very language they themselves make use of cries out against their professed phenomenism. For why speak of “we,” “ourselves,” etc., if there be no “we” or “ourselves” other than the perceptions, ideas, events, etc., referred to?