Page:The System of Nature.djvu/103

 increases his bulk — preserves him for a season, during which he is obliged to fulfil the task imposed on him. It is Nature, that in his journey through life, strews on the road those objects, those events; those adventures, that modify him in a variety of ways, that give him impulses which are sometimes agreeable and beneficial, at others prejudicial and disagreeable. It is Nature, that in giving him feeling, in supplying him with sentiment, has endowed him with capacity to choose, the means to elect those objects, to take those methods that are most conducive, most suitable, most natural, to his conservation. It is Nature, who when he has run his race, when he has finished his career, when he has described the circle marked out for him, conducts him in his turn to his destruction; dissolves the union of his elementary particles, and obliges him to undergo the constant, the universal law; from the operation of which nothing is exempted. It is thus, motion places man in the matrix of his mother; brings him forth out of her womb; sustains him for a season; at length destroys him; obliges him to return into the bosom of Nature; who speedily reproduces him, scattered under an infinity of forms; in which each of his particles run over again, in the same manner, the different stages, as necessary as the whole had before run over those of his preceding existence.

The beings of the human species, as well as all other beings, are susceptible of two sorts of motion: the one, that of the mass, by which an entire body, or some of its parts, are visibly transferred from one place to another; the other, internal and concealed, of some of which man is sensible, while some takes place without his knowledge, and is not even to be