Some of the leading naturalists of our day have lately expressed themselves clearly and tersely in this sense. The eminent physiologist Dubois Rey-mond denies that the connection between certain motions of certain atoms in the brain, and what he calls, the primal, undefinable and undeniable facts of consciousness, is at all conceivable. Professor Tyndall in his address on "The scope and limits of Scientific Materialism," explains his views with similar precision. Were our minds so expanded, strengthened and illuminated as to enable us to see and feel the very molecules of the brain; were we capable of following all their motions, all their groupings, all their electric discharges, if such there be; and were we intimately acquainted with the corresponding states of thought and feeling, we should be as far as ever from the solution of the problem. How are these physical processes connected by and with the facts of consciousness? I do not think the materialist is entitled to say that his molecular groupings and his molecular motions explain everything, in reality they explain nothing.... The problem of body and soul is as insoluble in its modern form as it was in the pre-scientific ages. Now since it is impossible to demonstrate that the powers of mind are a product of matter, the possibility undoubtedly remains that these powers may continue to exist even after their connection with the physical organism has been dissolved. If all the arguments that are commonly adduced in support of the doctrine of a future life fall short of their object, it is but just to add that every argument to the contrary is equally devoid of foundation. The doctrine of immortality cannot be disproved. Of the nature of soul we are in absolute ignorance we know nothing; what is more, we can know nothing At this point we touch the utmost boundary of human reason, and must be content to write mystery of mysteries.