The mind, after traversing its course of progress, after rising from sensation successively to the imaginative and the rational universal and from violence to equity, is bound in conformity with its eternal nature to re-traverse the course, to relapse into violence and sensation, and thence to renew its upward movement, to commence a reflux.
This is the philosophical meaning of Vico's "reflux," but not the exact manner in which we find it expressed in his writings, where the eternal circle is considered almost exclusively as exemplified in the history of nations, as a reflux in the civil affairs of man. Civilisation comes to an end in the "barbarism of reflection," which is worse than the primitive barbarism of sensation; for while the latter was not without a wild nobility, the former is contemptible, untrustworthy and treacherous; and thus it is necessary that this evil subtlety of malicious intellect should rust away through the long centuries of a new barbarism of sensation. We must however withdraw and purge the conception of "reflux" from historical facts and the sociological scheme, not only to explain the absolute and eternal character which Vico attributes to it, but also to justify the historical representation and sociological law founded upon it, and drawing their cogency primarily from it.
The laws of flux and reflux, laid down by the philosophers and politicians of Greece and of the Italian Renaissance, were founded no less than Vico's upon a philosophy, but upon a very superficial one; they assumed their object to possess external and empty political forms, and endeavoured to fix the succession of these forms upon data of experience or by vague reasonings. But Vico's object is the forms of culture, including in themselves all the activities of life, economy and law, religion and art, science and language, and referring them back to their inmost source, the human mind, he establishes their succession "according to the rhythm of the elementary forms of the mind." Thus all the learning which has been expended in comparing the Vician reflux with the theories of Plato or Polybius, Machiavelli or Campanella, is practically wasted: the more so that Vico (who, as we know, though often misunderstanding his predecessors cannot be accused of wishing to pass them over: in fact, where he thought he found parallel or identical ideas in them, he was apt to boast of the fact) felt no need of mentioning this point, or thought it unimportant. The "circular movement" (ἀνακύκλωσις) of Polybius, the economy of nature by which states alter, change and return to the same point, has been thought almost an anticipation of the eternal ideal history; but Vico sets Polybius with the others, when he asks the reader to consider "how (little) philosophers have thought with knowledge upon their principles of civil government, and with what (little) truth Polybius has reasoned upon its changes." Campanella connected his historical cycles with astrological laws; and Machiavelli conceives the catastrophe which opens the reflux thus: "When human craft and malignity have gone as far as they can go, it happens of necessity that the world purifies itself by one of the three methods (pestilence, famine and deluge, beside the human methods of new religions and languages) in order that men, having become few and chastened, may live more conveniently and become better." The one precedent to which Vico refers, but only to interpret it in a way altogether his own and in fact to give it a totally new content, is the ancient Egyptian tradition of the three successive ages of gods, heroes and men.