“Energy will not then be susceptible of transformation. This does not mean annihilation, a word without meaning, nor does it mean the absence of motion, properly speaking, since the same sum of energy will always exist in the form of atomic motion, but the absence of all sensible motion, of all differentiation, the absolute uniformity of conditions, that is to say, absolute death.” Such is the present statement of the science of mathematics. Experiment and observation prove that on the one hand the quantity of matter, and on the other hand the quantity of energy also, remains constant, whatever the change in form or in position; but they also show that the universe tends to a state of equilibrium, a condition in which its heat will be uniformly distributed. The heat of the sun and of all the stars seems to be due to the transformation of their initial energy of motion, to molecular impacts; the heat thus generated is being constantly radiated into space, and this radiation will go on until every sun is cooled down to the temperature of space itself. If we admit that the sciences of today, mechanics, physics and mathematics, are trustworthy, and that the laws which now control the operations of nature and of reason are permanent, this must be the fate of the universe. Far from being eternal, the earth on which we live has had a beginning. In eternity a hundred million years, a thousand million years or centuries, are as a day. There is an eternity behind us and before us, and all apparent duration is but a point. A scientific investigation of nature and acquaintance with its laws raises, therefore, the question already raised by the theologians, whether Plato, Zoroaster, Saint Augustine, Saint Thomas Aquinas, or some young seminarist who has just taken orders: “What was God doing before the creation of the universe, and what will he do after its end?” Or, under a less anthromorphic form, since God is unknowable: “What was the condition of the universe prior to the present order of things, and what will it be after this order has passed away?” Note that the question is the same, whether we admit a personal God, reasoning and acting toward a definite end, or, whether we deny the existence of any spiritual being, and admit only the existence of indestructible atoms and forces representing an invariable sum of energy. In the first case, why should God, an eternal and uncreated power, remain inactive? Or, having remained inactive, satisfied with the absolute infinity of his nature which nothing could augment, why did he change this state and create matter and force?