unavoidable defect in the principles of the science. But it has appeared sufficiently, from the discoveries of those who have consulted nature, and not their own imaginations, and particularly from what we learn from Sir Isaac Newton, _that the fault has lain in philosophers themselves, and not in philosophy_.” We are persuaded the day will come, when it will be seen that the despair of scepticism has been misplaced, not only with regard to natural knowledge, but also in relation to the great problems of the intellectual and moral world. It is true, that Plato failed to solve these problems; but his failure may be easily accounted for, without in the least degree shaking the foundations of our hope. The learned Ritter has said, that Plato felt the necessity imposed upon him, by his system, to reconcile the existence of evil with the perfections of God; but yet, as often as he approached this dark subject, his views became vague, fluctuating, and unsatisfactory. How little insight he had into it on any scientific or clearly defined principle, is obvious from the fact, that he took shelter from its difficulties in the wild hypothesis of the preëxistence of souls. But the impotency of Plato’s attempts to solve these difficulties, may be explained without the least disparagement to his genius, or without leading us to hope for light only from the world’s possession of better minds. In the first place, such was the state of mental science when Plato lived, that it would have been impossible for any one to reconcile the existence of evil with the perfections of God. It has been truly said, that “An attention to the internal operations of the human mind, _with a view to analyze its principles_, is one of the distinctions of modern times. Among the ancients scarcely anything of the sort was known.”—_Robert Hall_. Yet without a correct analysis of the powers of the human mind, and of the relations they sustain to each other, as well as to external objects and influences, it is impossible to shed one ray of light on the relation subsisting between the existence of moral evil and the divine glory. The theory of motion is “the key to nature.” It was with this key that Newton, the great high-priest of nature, entered into her profoundest recesses, and laid open her most sublime secrets to the admiration of mankind. In like manner, the true theory of action is the key to the intellectual world, by which its difficulties are to be laid open and its enigmas solved. Not possessing this key, it was as impossible for Plato, or for any other philosopher, to penetrate the mystery of sin’s existence, as it would have been, without a knowledge of the laws of motion, to comprehend the stupendous problem of the material universe.