Existence is a blessing to those beings only which are endowed with perception, and appears useless when bestowed upon dead matter, any farther than as it is subservient to beings which are conscious of their existence. Thus we find, from the bodies which lie under our observation, that matter is only made as the basis and support of animals, and that there is no more of the one than what is necessary for the exigence of the other.
There are some living creatures which are raised but just above dead matter; there are many others, but one remove from these, which have no other senses but those of feeling and taste; others have still an additional sense of hearing; others of smell, and again others of sight. It is wonderful to observe, by what a gradual progress life advances through a prodigious variety of species, before a creature is formed that possesses all these senses; and even among these, there is such a different degree of perfection in the senses which one animal enjoys beyond what appears in another, that, though the sense in different animals be distinguished by the same common denomination, it seems almost of a different nature. If, after this, we look into the several inward qualities of sagacity, or what is generally called instinct, we find them rising after the same manner imperceptibly one above another, and receiving additional improvements, according to the species in which they are implanted. This progress in nature is so very gradual, that what appears to us the most perfect of an inferior species, comes very near to the most imperfect, as we are accustomed to call it, of that which is immediately above it.
The exuberant and overflowing goodness of the SUPREME BEING, whose mercy extends to all his works, is plainly seen, as before observed, from his having made so very little matter, at least what falls within our knowledge, that does not swarm with life; nor is his goodness less visible in the diversity than in the multitude of living creatures. Had he only made one species of animals, none else could have enjoyed the happiness of existence; he has, therefore, included in his creation, every degree of life, every capacity of being. The whole chasm of nature, from a plant to a man, is filled up with diverse kinds of creatures, rising one above another, by such a gentle and easy ascent, that the little transitions and deviations from one species to the other are almost insensible. This intermediate space is so prudently managed, that there is scarce a degree of perception which does not appear in some one part of the animated world. Is the goodness or the wisdom of the DIVINE BEING more manifest in this his proceeding?