My argument is that this dragging in of the mind as making additions of its own to the thing posited for knowledge by sense-awareness is merely a way of shirking the problem of natural philosophy.

That problem is to discuss the relations _inter se_ of things known, abstracted from the bare fact that they are known.
Natural philosophy should never ask, what is in the mind and what is in nature.

To do so is a confession that it has failed to express relations between things perceptively known, namely to express those natural relations whose expression is natural philosophy.

It may be that the task is too hard for us, that the relations are too complex and too various for our apprehension, or are too trivial to be worth the trouble of exposition.

It is indeed true that we have gone but a very small way in the adequate formulation of such relations.