“There is no theory we may hold and no observation we can make that will retain so much as its old defective reference to the facts if the net be altered. Tinnitus, paraesthesias, hallucinations, delusions, confusions and disorientations intervene. Thus empiry [i.e., experience] confirms that if our nets are undefined, our facts are undefined, and to the “real” we can attribute not so much as one quality or “form”.”