In all these cases of perplexity there are, short of the refusal to think about our difficulties at all, only two courses open to us. We may answer the question at haphazard and as it suits our momentary caprice, or we may try to answer it on an intelligible principle. If we choose the second course, then clearly before we formulate our principle we must undertake a systematic and impartial inquiry as to what we really mean by the familiar distinction between “seems” and “is,” that is to say, a scientific inquiry into the general characteristics by which reality or real being is distinguished from mere appearance, not in some one special sphere of study, but universally. Now, such an inquiry into the general character of reality, as opposed to more or less unreal appearance, is precisely what is meant by Metaphysics. Metaphysics sets itself, more systematically and universally than any other science, to ask what, after all, is meant by being _real_, and to what degree our various scientific and non-scientific theories about the world are in harmony with the universal characteristics of real existence. Hence Metaphysics has been called “an attempt to become aware of and to doubt all preconceptions”; and again, “an unusually resolute effort to think consistently.” As we cannot, so long as we allow ourselves to think at all, avoid asking these questions as to what “is” and what only “seems,” it is clear that the attempt to dispense with metaphysical speculation altogether would be futile. We have really no choice whether we shall form metaphysical hypotheses or not, only the choice whether we shall do so consciously and in accord with some intelligible principle, or unconsciously and at random.