IT is with humility really unassumed--it is with a sentiment even of awe--that I pen the opening sentence of this work: for of all conceivable subjects I approach the reader with the most solemn--the most comprehensive--the most difficult--the most august.What terms shall I find sufficiently simple in their sublimity--sufficiently sublime in their simplicity--for the mere enunciation of my theme?I design to speak of the Physical, Metaphysical and Mathematical--of the Material and Spiritual Universe:--of its Essence, its Origin, its Creation, its Present Condition and its Destiny. I shall be so rash, moreover, as to challenge the conclusions, and thus, in effect, to question the sagacity, of many of the greatest and most justly reverenced of men.In the beginning, let me as distinctly as possible announce--not the theorem which I hope to demonstrate--for, whatever the mathematicians may assert, there is, in this world at least, no such thing as demonstration--but the ruling idea which, throughout this volume, I shall be continually endeavoring to suggest.My general proposition, then, is this:--In the Original Unity of the First Thing lies the Secondary Cause of All Things, with the Germ of their Inevitable Annihilation.In illustration of this idea, I propose to take such a survey of the Universe that the mind may be able really to receive and to perceive an individual impression.He who from the top of Ætna casts his eyes leisurely around, is affected chiefly by the extent and diversity of the scene. Only by a rapid whirling on his heel could he hope to comprehend the panorama in the sublimity of its oneness. But as, on the summit of Ætna, no man has thought of whirling on his heel, so no man has ever taken into his brain the full uniqueness of the prospect; and so, again, whatever considerations lie involved in this uniqueness, have as yet no practical existence for mankind.