§ 5. We may end this chapter by drawing certain conclusions which follow naturally from the acceptance of this doctrine. (1) It is clear that the result we have reached by analysis of what is implied in the “independent” existence of the physical order agrees with our previous conclusions as to the general structure of Reality. For we saw in our last Book that it seemed necessary to hold not only that Reality as a whole forms a single individual experience, but also that it is composed of members or elements which are themselves sentient experiences of varying degrees of individuality. And in our discussion of the unity of the thing we saw reason to hold that nothing but a sentient experience can be individual; thus we had already convinced ourselves that if there are things which are more than complexes of presentations arbitrarily thrown together for the convenience of human percipients in dealing with them as unities, those things must be sentient experiences on subjects of some kind. We have now inferred from the actual consideration of the physical order that it does, in point of fact, consist of things of this kind. Our result may thus be said to amount in principle to the logical application to physical existence of the previously ascertained conclusion, that only what is to some degree truly individual can be real. It is interesting to contrast with this consequence of our metaphysical attempt to interpret the course of physical nature, the result which inevitably follows from consistent adherence to the procedure of descriptive science. The whole procedure of descriptive science depends upon our willingness to shelve, for certain purposes, the problem wherein consists the reality of the physical order, and to concentrate our interest upon the task of adequately and with the greatest possible economy of hypothesis describing the system of presented contents in which it reveals itself to our senses. For purely descriptive purposes, our sole interest in the physical order is to know according to what laws of sequence one presented content follows upon another. Hence, so long as we can establish such laws of connection between presented contents, it is for purely scientific purposes indifferent how we imagine the Reality in which the sequence of presentation has its ground. Whether we think of it as a system of finite subjects, the will of a personal Deity, a complex of primary qualities, or an unknown substratum, or whether we decline to raise any question whatever about the matter, the results are the same, so long as our sole object is to exhibit the sequence of presented sense-contents as regulated by laws which admit of calculation. Science can go its way in entire indifference to all these alternative metaphysical interpretations of the Reality which is behind the phenomenal order.