Ne regio foret ulla suis animalibus orba.
Our sagacious author believes that the air and even the purest aether have their denizens as well as the water and the earth. But supposing that there were places without animals, these places might have uses necessary for other places which are inhabited. So for example the mountains, which render the surface of our globe unequal and sometimes desert and barren, are of use for the production of rivers and of winds; and we have no cause to complain of sands and marshes, since there are so many places still remaining to be cultivated. Moreover, it must not be supposed that all is made for man alone: and the author is persuaded that there are not only pure spirits but also immortal animals of a nature akin to these spirits, that is, animals whose souls are united to an ethereal and incorruptible matter. But it is not the same with animals whose body is terrestrial, composed of tubes and fluids which circulate therein, and whose motion is terminated by the breaking of the vessels. Thence the author is led to believe that the immortality granted to Adam, if he had been obedient, would not have been an effect of his nature, but of the grace of God.
9. Now it was necessary for the conservation of corruptible animals that they should have indications causing them to recognize a present danger, and giving them the inclination to avoid it. That is why what is about to cause a great injury must beforehand cause pain such as may force the animal to efforts capable of repulsing or shunning the cause of this discomfort, and of forestalling a greater evil. The dread of death helps also to cause its avoidance: for it if were not so ugly and if the dissolution of continuity were not so painful, very often animals would take no precautions against perishing, or allowing the parts of their body
to perish, and the strongest would have difficulty in subsisting for a whole day.
God has also given hunger and thirst to animals, to compel them to feed and maintain themselves by replacing that which is used up and which disappears imperceptibly. These appetites are of use also to prompt them to work, in order to procure a nourishment meet for their constitution, and which may avail to invigorate them. It was even found necessary by the Author of things that one animal very often should serve as food for another. This hardly renders the victim more unhappy, since death caused by diseases is generally just as painful as a violent death, if not more so; and animals subject to being preyed upon by others, having neither foresight nor anxiety for the future, have a life no less tranquil when they are not in danger. It is the same with inundations, earthquakes, thunderbolts and other disorders, which brute beasts do not fear, and which men have ordinarily no cause to fear, since there are few that suffer thereby.
10. The Author of Nature has compensated for these evils and others, which happen only seldom, with a thousand advantages that are ordinary and constant. Hunger and thirst augment the pleasure experienced in the taking of nourishment. Moderate work is an agreeable exercise of the animal's powers; and sleep is also agreeable in an altogether opposite way, restoring the forces through repose. But one of the pleasures most intense is that which prompts animals to propagation. God, having taken care to ensure that the species should be immortal, since the individual cannot be so here on earth, also willed that animals should have a great tenderness for their little ones, even to the point of endangering themselves for their preservation. From pain and from sensual pleasure spring fear, cupidity and the other passions that are ordinarily serviceable, although it may accidentally happen that they sometimes turn towards ill: one must say as much of poisons, epidemic diseases and other hurtful things, namely that these are indispensable consequences of a well-conceived system. As for ignorance and errors, it must be taken into account that the most perfect creatures are doubtless ignorant of much, and that knowledge is wont to be proportionate to needs. Nevertheless it is necessary that one be exposed to hazards which cannot be foreseen, and accidents of such kinds are inevitable. One must often be mistaken in one's judgement, because it is not always permitted
to suspend it long enough for exact consideration. These disadvantages are inseparable from the system of things: for things must very often resemble one another in a certain situation, the one being taken for the other. But the inevitable errors are not the most usual, nor the most pernicious. Those which cause us the most harm are wont to arise through our fault; and consequently one would be wrong to make natural evils a pretext for taking one's own life, since one finds that those who have done so have generally been prompted to such action by voluntary evils.
11. After all, one finds that all these evils of which we have spoken come accidentally from good causes; and there is reason to infer concerning all we do not know, from all we do know, that one could not have done away with them without falling into greater troubles. For the better understanding of this the author counsels us to picture the world as a great building. There must be not only apartments, halls, galleries, gardens, grottoes, but also the kitchen, the cellar, the poultry-yard, stables, drainage. Thus it would not have been proper to make only suns in the world, or to make an earth all of gold and of diamonds, but not habitable. If man had been all eye or all ear, he would not have been fitted for feeding himself. If God had made him without passions, he would have made him stupid; and if he had wished to make man free from error he would have had to deprive him of senses, or give him powers of sensation through some other means than organs, that is to say, there would not have been any man. Our learned author remarks here upon an idea which histories both sacred and profane appear to inculcate, namely that wild beasts, poisonous plants and other natures that are injurious to us have been armed against us by sin. But as he argues here only in accordance with the principles of reason he sets aside what Revelation can teach. He believes, however, that Adam would have been exempted from natural evils (if he had been obedient) only by virtue of divine grace and of a covenant made with God, and that Moses expressly indicates only about seven effects of the first sin. These effects are:
1. The revocation of the gracious gift of immortality.
2. The sterility of the earth, which was no longer to be fertile of itself, save in evil or useless herbs.