the solar system to be operated upon by the law which he had discovered. He would next ask himself, How came this law of gravitation to exist? That it must have had an origin, must have proceeded from some lawgiver competent to make and enforce it, would be a conclusion to which he would be irresistibly led, for the very idea of a law implies that it is a command proceeding from an authority and power capable of ordaining and executing it. When it is said that a law is a rule of action ordained by a supreme power, which is perhaps the most familiar as it is the most exact definition, the idea of a command and of a power to enforce it is necessarily implied. This is just as true of a physical as it is of a moral law; of a law that is to govern matter as of a law that is to govern moral and accountable beings. Both proceed from a supreme authority and power, and both are commands. There is, however, one distinction between a moral law and a law of Nature, which relates to the mode in which we arrive at a knowledge of the law; a distinction which our inquirer would learn in the course of his investigations. We infer the existence of a law of Nature, or a law designed to operate upon matter, from the regularity and uniformity of certain physical phenomena. As the phenomena occur always in the same way we infer it to be an ordinance of Nature that they shall occur in that way. But the moral phenomena exhibited by the actions of men have not this regularity and uniformity. They are sometimes in accordance with and sometimes grossly variant from any supposed rule of moral action. We can not, therefore, deduce a moral law from our observation of the actions of the beings whom it was designed to govern, but we must discover it from the rules of right reason and from such information as has been given to us by whatever revelation may have come to us from another source than our own minds. But this distinction between the modes of reaching a knowledge of physical and moral laws does not apply to the authority from which they have proceeded. Both of them being commands, or fixed rules of action, both must have had an enacting authority. We learn the one by observing the phenomena of Nature. We learn the other from reason and revelation.