INTRODUCTION. THE present age is one of very rapid progress in almost all branches of knowledge. Like a wave swelling as it advances shoreward, this progress has violently transformed whole regions of thought, while it has repeatedly invaded others not heretofore deemed accessible to such catastrophes. Presuming upon a soil of great natural richness, the inhabitants of these latter regions had for a long series of years given themselves up to a species of husbandry which was beginning at length to be detrimental in its effects. It thus came to pass that while the immediate result of each inundation was a sudden alarm and consequent confusion, yet nevertheless a fertilising residuum was always left behind, together with a very plain intimation that no region of thought can permanently flourish if it be entirely cut off from any of the intellectual influences around it. Suchlike, we take it, have been the results of the recent great floods of intellectual energy, A much of them seemingly subversive, which have repeatedly invaded the region occupied by the followers of Christianity. At present there is no book more read than the Bible, no life more deeply studied and discussed than the life of Christ. There is probably a greater amount of earnest attention devoted to these subjects than to any other branch of human inquiry. Nevertheless there is great great confusion, and an almost despairing outcry from many of the inhabitants of the Christian region. It is imagined that fences and landmarks have disappeared, and that at length the rising tide is about to attack, as it has long threatened, the very lives and holdings of the community. It will be our endeavour to reassure these somewhat over-timid people. Being students of physical science, we will try to gauge the strength of the tide, and more especially of the forces which give it motion, and endeavour to convince those who are sufficiently calm to receive conviction, that there neither is nor can be any real danger to their lives and holdings from the violence of the waters; but that, on the contrary, they will ultimately receive a blessing from that which will remain behind after the present confusion has disappeared. Skin for skin,' said a certain evil one, yea all that a man hath will he give for his life,' and the proverb is true (with a modifica tion) as regards the life of the soul, no less than as regards that of the body. Take away all hope of a future state,-appear to demonstrate, if not with absolute certainty, yet with an approach to it, that such a condition of things is antagonistic to well-understood scientific principles, and we feel certain that the effect upon humanity would be simply disastrous. At any rate, those who propound an argument of this kind must reasonably expect determined opposition from the followers of religion. Let us here, before proceeding further, take the opportunity of stating that we discuss only the physical aspects of the argument regarding a future state. Being neither metaphysicians nor moral philosophers, we leave to others more competent than we can be the argument which may be based upon the universal craving among the intelligent races of mankind for a life beyond the grave. In the fourth and following editions of our work, while we have not materially altered our argument, we have recast to some extent the shape in which it was first put before the reader, and this recasting has taken a more definite form in our present edition. The large amount of friendly criticism which our work has called forth has convinced us that we did not at first sufficiently separate between certain conclusions which inevitably flowed from our argument, and certain others which, while deriving their strength from a totally different quarter, were yet not inconsistent with the former, but even, it might be, supported by them. The consequence has been that we have found ourselves credited with attempts which were very far from our thoughts, such, for instance, as the endeavour to deduce Christian theological doctrine from mere physical considerations. We have therefore thought it desirable to bring in review before the reader, in this introductory chapter, the fundamental points of our argument, more especially as in what follows we may not always be able without an undesirable formality to keep separate the foundation and the superstructure. In his justly renowned Analogy, Bishop Butler begins with a chapter on a future life. He says with great truth that if there is an idea that death will be the destruction of living powers, that idea must arise either from the reason of the thing or the analogy of nature. 'But it does not arise (he proceeds to say) from the reason of the thing; for we do not know what death is. Again, we do not know on what the existence of our living powers depends; for we.see them suspended in sleep, for example, or |