In the _second place_, the system of a succession of races of animals on earth, which death alone would render possible, secures a much greater collective amount of happiness than a single race of animals, endowed with earthly immortality. I sustain this position by three arguments. The first is, that young animals enjoy more, in the same period of time, than those more advanced in age. This may result, in part, in the present organization of animals, from the superior health and vigor enjoyed by the young. But it is due, also, in part, and largely, to the novelty of the scenes presented in early life. And so far as it results from the latter cause, it proves that a succession of races would enjoy more than a single race continued indefinitely, because the successive races would always be comparatively young. A single continuous race might, indeed, be supposed always possessed of the unabated vigor and health of youth; but, of necessity, objects must soon lose the charm of novelty, and, therefore, produce less of enjoyment. The second argument is, that a succession of races admits of the contemporaneous existence of a greater number of species than could coexist were none removed by death. If only one undying race occupied the globe, it must subsist exclusively on vegetable food. Whereas much the largest part of the species that now live are carnivorous or omnivorous. All the enjoyment of these flesh-eating animals is, therefore, so much clear gain to the stock of happiness, with the exception of the suffering which death inflicts. Now, but few of the inferior animals perish by disease. Some die by old age, and these suffer almost nothing. But the greater part are suddenly destroyed by the violent assault of the carnivorous races. And as the pangs of death are momentary, and there are no anticipations of its approach, nor sunderings of the ties of affection, nor dread of an hereafter, the suffering endured must be an exceedingly small drawback upon the enjoyment of the whole life. It is far less than it would be, if animals were left to perish by famine, or by slow degrees, from deficient nourishment; so that the existence of the carnivorous races, seeming at first view intended to convert the world into a vast Golgotha, does in fact add greatly to the amount of enjoyment, because it so prodigiously multiplies the number of species of animals, and lessens the sufferings of death. In the third place, death exerts a salutary moral influence upon man, and, as a consequence, swells the amount of his happiness. And although this consideration affects only one species, yet man's position on the scale of being makes his happiness an object of no small importance.