Pure spirit is the Life-principle considered apart from the matrix in which it takes relation to time and space in a particular form. In this aspect it is pure intelligence undifferentiated into individuality. As pure intelligence it is infinite responsiveness and susceptibility. As devoid of relation to time and space it is devoid of individual personality. It is, therefore, in this aspect a purely impersonal element upon which, by reason of its inherent intelligence and susceptibility, we can impress any recognition of personality that we will. These are the great facts that the mental scientist works with, and the student will do well to ponder deeply on their significance and on the responsibilities which their realization must necessarily carry with it. IV. SUBJECTIVE AND OBJECTIVE MIND. Up to this point it has been necessary to lay the foundations of the science by the statement of highly abstract general principles which we have reached by purely metaphysical reasoning. We now pass on to the consideration of certain natural laws which have been established by a long series of experiments and observations, the full meaning and importance of which will become clear when we see their application to the general principles which have hitherto occupied our attention. The phenomena of hypnosis are now so fully recognized as established scientific facts that it is quite superfluous to discuss the question of their credibility. Two great medical schools have been founded upon them, and in some countries they have become the subject of special legislation. The question before us at the present day is, not as to the credibility of the facts, but as to the proper inferences to be drawn from them, and a correct apprehension of these inferences is one of the most valuable aids to the mental scientist, for it confirms the conclusions of purely _a priori_ reasoning by an array of experimental instances which places the correctness of those conclusions beyond doubt.