GEORGE GEORGE STUART FULLERTON, A System of Metaphysics. 233 Meanwhile the physical system has its integrity, and it is not every table of the imagination that can find admission to it " I do not believe the table in the next room to exist merely because [i.e.., in that] the perception of it is in my mind ". The imaginal table figures to the mind as a real part of the physical system on the understanding (which as regards our consciousness is in the first instance entirely tacit) that it could, under appropriate cir- cumstances, be exchanged for sensation. When the mind does come to mark the difference between the imaginal and the sensory it recognises at once that " the table as seen ... is actually in the setting in which things must be if they are to constitute elements in the external world " in the physical system and that the imaginal table is not in such a setting. The setting is the all-important fact. For what is the test by which sensation shall be distinguished ? Sensation is not always more vivid than imagination. We have to turn to "the only ultimate criterion, a recognition of the way in which the experience behaves, of the place among our other experiences which it takes and maintains, and thus to decide upon the class to which it rightly belongs ". "We must discover whether it takes its place among those ele- ments of our experience which so connect themselves together as to form what we recognise as the system of material things." For there is an orderliness in this system lacking in our other experiences. Thus the test of membership in the class of sensa- tions and the test of membership in the physical system prove to be in one stage of analysis the same ; namely, their presenting themselves in a certain recognisable order independent of the will. Imaginal tables, etc., do not in their behaviour manifest this order. When one to whom an imaginal table has been, in point of con- tent, on precisely the same footing of objectivity as the table of sense, is led in any case to remark the fact that it is merely imaginal i.e., probably in some sense fainter and certainly not in the order of involuntary experiences he comes to take the imaginal edition as secondary. " He sees that the imaginary constituents of the world of real things which he finds in his experience do not take their place in that construction as imaginary elements but as representative of sensational elements." "They are important to us primarily on account of the function which they perform," that is, as guiding our wills in relation to the sensations for which they stand. They are representatives in effect blind representatives. It was for this reason that in the economy of our natural thinking we were trained to "pay atten- tion " only to their content, ignoring the imaginal quality ; for of such content, in its determinate context, is the physical world com- posed. When we see the representative function of imagination and the possibility of misrepresentation, we have drawn the dis- tinction between things and our ideas of them. But if the physical world does not consist of our imaginations, neither does it consist of our sensations. Our actual sensations