If we turn now from the fabulous traditions of the ancient world, we still find an absolute truth proclaimed by its sages; one that affirms the existence of an eternal law--_quiddam æternum_--which was called the natural law, and which serves as a criterion whereby to judge the worth of the laws promulgated by man. Cicero declares it absurd to consider right everything set down in the constitutions or the laws.[50] And he is careful to add that neither is public opinion any more competent to determine the right.[51] The sovereign law, therefore--that which no human law may violate without the penalty of becoming void--has God himself for its author. The laws of states may be unjust and abominable, and, by consequence, bind no one. There is, on the other hand, a natural law, the source and measure of other laws, originating before all ages, before any law had been written or any city built.[52] This doctrine, to support which I have designedly cited only pagan authors, is also that of Catholic theologians; for example, S. Thomas and Suarez. But the philosophical school of the last century has so perverted the meaning of the term _nature--law of nature_, that certain Catholic authors (M. de Bonald, for instance) have scrupled to use the consecrated term. It is necessary, then, to explain its true sense. IV.--NATURAL LAW ACCORDING TO PAGAN PHILOSOPHERS. The nature of a being is that which constitutes its fitness to attain its end. The idea, therefore, which a person has of the nature of man, by consequence determines that which he will have of his end, and hence of the rule which should govern his actions. The materialists, for example, who deny the immortality of the soul, and whose horizon is bounded by the limits of the present life, are able to teach only a purely epicurean or utilitarian morality. They cannot consistently plead a motive higher than an immediate, or at least a proximate, well-being; for, what is more uncertain than the duration of our life? In the strikingly anti-philosophic language of the XVIIIth century, _the state of nature_ was a hypothetical state, at once innocent and barbarous, anterior to all society. It is to society that this theory attributes the disorders of man and the loss of certain primitive and inalienable rights which the sect of pseudo-philosophers boasted of having regained, and by the conquest whereof the corrupted and doting France of 1789 was prostrated. The philosophers of antiquity, on the contrary, notwithstanding their numerous errors, and despite the polytheism which they exteriorly professed, had arrived at so profound a knowledge of man and his nature that the fathers and doctors of the church have often spoken of the discoveries of their intellect as a kind of _natural revelation_ made to them by God.[53]