In his ‘Preface’ to Laws of Media, Eric McLuhan records:

My father died before we could work out in detail how his new discoveries related to the labours of Vico and Bacon. He knew the relations were there, and his intuitions had never played him false. It fell to me to do the tidying-up and to ready the book for the press. The key to the whole business is sensibility, as the serious poets and artists (and grammarians) have always maintained. Vico in particular targeted ‘the modification of our own human minds’ as the crucial area, while he cast about for a way to read and write the ‘mental dictionary’. Then the relation between Bacon’s Idols and Vico’s Axioms surfaced¹ — bias of perception — and the job was near done. Bacon called his book the Novum Organum (…), the New Science; Vico called his the Scienza Nuova, the New Science; I have subtitled ours The New Science. On reflection, I am tempted to make that the title (…) for it should stand as volume three of a work begun by Sir Francis Bacon and carried forward a century later by Giambattista Vico. (x-xi)

Laws of Media details the Bacon-Vico relation as follows:

When determining the principles on which his Scienza Nuova would rest, Giambattista Vico, the last great pre-electric grammarian, decided to use cultures themselves as his text: “We must reckon as if there were no books in the world.”² In shunning conventional science and returning to direct observation of the page of Nature, Vico pursued the same course Francis Bacon had charted in the Novum Organum... (Laws of Media, posthumous, 215)

Vico (…) begins by reiterating and updating Bacon’s [four] Idols as his own first four Axioms. The first four axioms constitute the basis of Vico’s elements and, says Vico, “give us the basis for refuting all opinions hitherto held about the principles of humanity” (New Science, §163). “These four axioms express a theory of ignorance which we need in order to acquire a doctrine of truth concerning the nature of humanity.”³ (Laws of Media, 11)

The ‘myth of objectivity’, a result of visual bias, belongs to the ‘Idols of the Theatre’ or what Giambattista Vico termed ‘the conceit of scholars’ in his fourth axiom. Vico was merely following [Bacon’s previous] instructions when, at the outset of his Scienza Nuova, he set out his [four] ‘elements’ or ‘axioms’, for Bacon had prefaced his account of his [four] ‘Idols’ with these words: “The formation of ideas and axioms by true induction is no doubt the proper remedy to be applied for the keeping off and clearing away of idols. To point them out, however, is of great use for the doctrine of idols is to the interpretation of nature what the doctrine of the refutation of sophisms is to common logic.”⁴ (Laws of Media, 83-84)

[The first of Bacon’s Idols,] the Idols of the Tribe, and Vico’s first axiom, specify the general bias of sensibility (…) as a pollution of exact observation which must be allowed for. (…) “The Idols of the Tribe have their foundation in human nature itself, and in the tribe or race of men. For it is a false assertion that the sense of man is the measure of things. On the contrary, all perceptions, as well of the sense as of the mind, are according to the measure of the individual and not according to the measure of the universe. And the human understanding is like a false mirror, which, receiving rays irregularly, distorts and decolors the nature of things by mingling its own nature with it.”⁵ (Laws of Media, 84)

Vico’s [corresponding] first axiom is this: “Because of the indefinite nature of the human mind, wherever it is lost in ignorance, man makes himself the measure of all things. This axiom explains those two common human traits, on the one hand that rumor grows in its course (fama crescit eundo). On the other that rumor is deflated by the presence of the thing itself (minuit praesentia famam). In the long course that rumor has run from the beginning of the world it has been the perennial source of all the exaggerated opinions which have hitherto been held concerning remote antiquities unknown to us, by virtue of that property of the human mind noted by Tacitus in his Life of Agricola, where he says that everything unknown is taken for something great (omne ignotum pro magnifico est).”⁶ (Laws of Media, 84)

[The second of Bacon’s Idols], the Idols of the Cave, and Vico’s second axiom, pinpoint intellectual laziness and conceptual dogmatism as distorting influences (…) “The Idols of the Cave are the idols of the individual man. For everyone (besides the errors common to human nature in general) has a cave or den of his own. which refracts and discolors the light of nature, owing either to his own proper and peculiar nature or to his education and conversation with others, or to the reading of books, and the authority of those whom he esteems and admires or the like. So that the spirit of man (according as it is meted out to different individuals) is in fact a thing variable and full of perturbation, and governed as it were by chance. Whence it was well observed by Heraclitus that men look for sciences in their own lesser worlds, and not in the greater or common world.”⁷ This Idol takes its name from the cave in the Republic of Plato (Book VII). Vico notes (axiom two): “It is another property of the human mind that whenever men can form no idea of distant and unknown things they judge them by what is familiar and at hand. This axiom points to the inexhaustible source of all the errors about the beginnings of humanity that have been adopted by entire nations and by the scholars For when the former began to take notice of them and the latter to investigate them, it was on the basis of their own enlightened, cultivated and magnificent times that they judged the origins of humanity, which must nevertheless by the nature of things have been small, crude and quite obscure.”⁸  (Laws of Media, 84)

[The third of Bacon’s Idols], the idols of the Marketplace — Vico’s ‘conceit of nations’ — arise in the ‘intercourse and association of men with each other’ (…): “There are also idols formed by the intercourse and association of men with each other, which I call Idols of the Market-place, on account of the commerce and consort of men there. For it is by discourse that men associate and words are imposed according to the apprehension of the vulgar. And therefore the ill and unfair choice of words wonderfully obstructs the understanding. Nor do the definitions or explanations wherewith in some things learned men are wont to guard and defend themselves, by any means set the matter right. But words plainly force and overrule the understanding, and throw all into confusion, and lead men away into numberless empty controversies and idle fancies.”⁹ Vico translates this into his third axiom as follows: “As for the conceit of the nations, we have heard that golden saving of Diodorus Siculus. Every nation, according to him, whether Greek or barbarian, has had the same conceit that it before all other nations invented the comforts of human life and that its remembered history goes back to the very beginning of the world.”¹⁰ (Laws of Media, 84-85)

Fourth and last, Bacon cites the Idols of the Theatre ‘which have immigrated into men’s minds from the various dogmas of philosophies’ — Old Science. These Vico terms ‘conceit of scholars’ whose sciences have neither real antiquity of knowledge nor knowledge of antiquity, being cut off from tradition This conceit shores up its own narrow version of thought by claiming that what it knows is what all learning has always been about. (…) [Bacon]: “Lastly, there are the Idols which have immigrated Into men’s minds from the various dogmas of philosophies, and also from wrong laws of demonstration These I call Idols of the Theater; because in my judgment all the received systems are but so many stage-plays, representing worlds of their own creation after an unreal and scenic fashion. Nor is it only of the systems now in vogue, or only of the ancient sects and philosophies, that I speak, for many more plays of the same kind may yet be composed and in like artificial manner set forth; seeing that errors the most widely different have nevertheless causes for the most part alike. Neither again do I mean this only of entire systems, but also of many principles and axioms in science, which by tradition, credulity, and negligence have come to be received”¹¹ Vico renders this in his fourth axiom: “To this conceit of the nations there may be added that of the scholars, who will have it that whatever they know is as old as the world. This axiom disposes of all the opinions of the scholars concerning the matchless wisdom of the ancients”.¹² (Laws of Media, 85)