The reason why I have introduced this subject is this: Later philosophers, disciples of Aristotle, assume that he has proved the Eternity of the Universe, and most of those who believe that they are philosophers blindly follow him in this point, and accept all his arguments as conclusive and absolute proofs. They consider it wrong to differ from Aristotle, or to think that he was ignorant or mistaken in anything. For this reason, taking their standpoint, I show that Aristotle himself did not claim to have proved the Eternity of the Universe. He says in his book Physics (viii., chap. i.) as follows: “All the Physicists before us believed that motion is eternal, except Plato, who holds that motion is transient; according to his opinion the heavens are likewise transient.” Now if Aristotle had conclusive proofs for his theory, he would not have considered it necessary to support it by citing the opinions of preceding Physicists, nor would he have found it necessary to point out the folly and absurdity of his opponents. For a truth, once established by proof, does neither gain force nor certainty by the consent of all scholars, nor lose by the general dissent. We further find that Aristotle, in the book The Heavens and the World, introduces his theory of the Eternity of the Universe in the following manner: “Let us inquire into the nature of the heavens, and see whether they are the product of something or not, destructible or not.” After this statement of the problem, he proceeds to cite the views of those who hold that the heavens have had a beginning, and continues thus: “By doing this, our theory will be most plausible and acceptable in the opinion of profound thinkers; and it will be the more so, when, as we propose, the arguments of our opponents are first heard. For if we were to state our opinion and our arguments without mentioning those of our opponents, our words would be received less favourably. He who desires to be just must not show himself hostile to his opponent; he must have sympathy with him, and readily acknowledge any truth contained in his words; he must admit the correctness of such of his opponent’s arguments as he would admit if they were in his own favour.” This is the contents of the words of Aristotle. Now, I ask you, men of intelligence, can we have any complaint against him after this frank statement? Or can any one now imagine that a real proof has been given for the Eternity of the Universe? Or can Aristotle, or any one else, believe that a theorem, though fully proved, would not be acceptable unless the arguments of the opponents were fully refuted? We must also take into consideration that Aristotle describes this theory as his opinion, and his proofs as arguments. Is Aristotle ignorant of the difference between argument and proof? between opinions, which may be received more or less favourably, and truths capable of demonstration? or would rhetorical appeal to the impartiality of