How (and, indeed, did) the print revolution create a market of ideas? Summed up in one word, the best answer is ‘messily’.

The term ‘marketplace of ideas’ was coined as a paraphrase of John Stuart Mill’s argument in On Liberty: the more freely ideas flow, the easier it is for good ones to rise to the top. This noble, humanistic sentiment has had a lasting influence on histories of the print revolution in early modern Europe. As communication became easier and faster, so the story goes, it became ever harder for centralised authorities to control. Similar hopes have been renewed in more recent times: it was a commonplace of reporting on the Arab Spring to hail social media as a powerful new weapon against oppressive regimes.

But the course of technological change rarely runs smooth. Since the heady days of 2010, observers have spent ever more time worrying about the downsides of social media: fake news, misinformation, echo chambers. Just like our early-modern forebears, we have started to recognise that the sudden acceleration and broadening proliferation of political discussion poses dangers as well as opportunities. Exploring the parallels between these two communication revolutions, the early modern and the modern, can help us better understand the subtleties – and messiness – of this process.

Print certainly did open up political discussion to a broad range of participants beyond traditional elites. It was major commercial centres, such as the Republic of Venice, that emerged as Europe’s crucial centres of printing and the nascent ‘culture of news’. Venice’s large merchant class provided an ideal market for increasingly affordable print literature. As we know from Shakespeare’s Othello and The Merchant of Venice, this was a highly mobile, multi-racial and multi-ethnic society. Vittore Carpaccio’s painting The Miracle of the Cross at the Rialto Bridge (c. 1494–96) depicts the Venetian centre of trade and information in all its bustling energy. At the front, we see a black gondolier, while further back, we find men wearing turbans, probably visiting from the Ottoman Empire. If you wanted to know news from across Europe, the Middle East and beyond, you needed informants in Venice.

News sheets known as avvisi were regularly distributed in manuscript, before some of their contents found their way into printed pamphlets, which could be circulated beyond the city. People with both a professional and amateur interest in the sale of information would gather in groups to exchange the latest reports from abroad. These gatherings – like those visible in the background of another Carpaccio painting inspired by the Venetian cityscape, his Arrival of the English Ambassadors (c. 1495-1500) – were given their own nickname: bozzoli, the word for the cocoon of a silkworm, to which these closed huddles bore a resemblance. Information became a valuable commodity, and anyone could gather and trade in it.

By 1612 the ‘culture of news’ had become so central to Venetian culture that it was already being parodied by the satirist Traiano Boccalini in his work Advertisements from Parnassus. The book comprises a set of imagined ‘news reports’ from Parnassus, the fictional court of the Roman god Apollo, which is populated by the great and good of European history. Boccalini’s vignettes bear some resemblance to the modern comedy sketch. In one such ‘advertisement’, the 16th-century Flemish political writer Justus Lipsius is put on trial for idolatry, for his worship of the Roman political historian Cornelius Tacitus. Boccalini mocks those, like Lipsius, who had forged careers as so-called experts in politics, on the basis of reading a few printed books.

In making political knowledge more widely available to people at all levels of society, the early-modern culture of news was something of a democratising force. But it was evident from the start that this opening up of political conversation also created new opportunities for misinformation, leaks and other kinds of skulduggery. Texts were printed under false names, places of printing were disguised, and works were falsely attributed to enemies to discredit them.

Despite our escalating modern debates about free speech, fake news, and post-truth politics, there has still been relatively little consideration of how the internet revolution has changed the structure of political debate. That is to say, how it changed the ways in which ideas are circulated.

A crucial and often overlooked factor which caused confusion in the wake of both the print revolution and the internet revolution today, is the way that comments and ideas are rapidly removed from their original context. Political speech is usually aimed at a particular audience, making effective use of contextual knowledge of this audience to get their message across. If ideas move further and faster, there is a greater chance that they reach an audience for which they were not intended, and thus end up having unplanned and unwanted effects.

In the early modern period, many found themselves caught out by this sudden acceleration. Just like today, a comment that started as a joke among friends could – taken out of context – suddenly become a public scandal.

One of those who discovered this the hard way was the English ambassador to Venice, Sir Henry Wotton. While passing through Augsburg in 1604, Wotton wrote a punning definition of the word ‘ambassador’ in an acquaintance’s book of autographs. An ambassador, he wrote, is ‘an honest man sent to lie abroad for the good of his country’.

The joke was swiftly seized on by England’s enemies. The Catholic polemicist Caspar Schoppe printed it as part of a vitriolic pamphlet attack on the government of James VI & I of England. The king ordered Wotton to issue an immediate apology. But the damage to Wotton – and England’s – reputation was done.

Like many of the victims of ‘cancellation’ today, Wotton had been caught out by the fact that what he thought was said in a private setting rapidly became available to an international audience. We might be tempted to put this down as simply rather stupid, just as it is stupid today for candidates running for office not to delete old tweets: an edgy joke is always a hostage to fortune. But it is easily done, especially when a hidden camera or microphone opens up a seemingly private occasion to the world.

The process of ideas being taken out of context also had more subtle manifestations. Perhaps the most interesting is the way that the removal of context can fuel polarisation. As more people are exposed to a wider range of their opponents’ arguments, especially in less subtle forms, the more entrenched in their existing views they are likely to become. When early-modern people found their opponents making blunt arguments, they were delighted – and gleefully reprinted them, recognising the potential for extreme views to backfire.

Around the year 1600, the Italian Dominican friar Tommaso Campanella wrote a manuscript work of political advice addressed to the Spanish monarchy, in which he included suggestions for crushing Flemish opposition to Spanish rule in the Low Countries. It was this section of his work that received the widest print dissemination. Perhaps surprisingly, this was thanks to the Flemish opponents of Spain themselves, who extracted and republished the relevant section of the work at Leiden in 1617, recognising that it would help galvanise opposition. This curtailed text was soon reprinted in multiple translations (Flemish, Latin, and German). Campanella’s tract had proved highly successful – in achieving entirely the opposite aim to that he had intended.

The 17th century saw a widespread repurposing of materials produced to support one side of a dispute being used to support the other. Another intriguing example is what appears to be a celebratory print depicting Pope Paul V (a copy can viewed through the British Museum’s online image collection, Museum Number 1872,0511.1276). The Pope’s portrait sits in the middle of the image. To his right and left, crowns hang from a wooden frame. He is attended by four female allegorical figures and a host of cherubs, who blow trumpets and wave banners with slogans of biblical praise. The inscription below is equally triumphant: ‘For Paul V, Vice-God, most invincible Monarch of the Christian Republic and most zealous preserver of papal omnipotence’ (Paulo. V. Vice-Deo Christianae Reipublicae Monarchae invictissimo, pontificiae omnipotentiae conservatori acerrimo).

Copies survive in various European archives, including the British Museum, the Rijksmuseum in Amsterdam, and multiple Oxford and Cambridge college libraries, but here we get a clue that all might not quite be as it seems: these are archives of the Protestant, not the Roman Catholic, world. Though these prints look like a celebration, their actual purpose was rather different. In fact, they were printed as an insert at the start of a book, the The Mystery of Iniquity of 1611, written by the leading French Protestant and so-called ‘Pope of the Huguenots’, Philippe Duplessis-Mornay (1549-1623), who claimed to prove that the Pope was the Antichrist.

Why include this rather official looking portrait of the Pope in a fervently anti-papal book? Where had this come from? Apparently, according to a note in French at the top, the print came from Rome itself. It had reportedly been published as a frontispiece to a set of theological theses, defending papal power. A description was sent to France by the Venetian theologian and critic of the papacy, Paolo Sarpi (1552-1623).

For Sarpi, the print was alarming proof of the Pope’s overweening ambition. Most worrying was the fact that the Pope’s image was placed between two posts to which the crowns of secular rulers were nailed like trophies: to the Pope’s right were the crowns of Western European monarchs, including the distinctive imperial crown of the Holy Roman Emperor and the pointed corno of the Venetian doge; to his left were the crowns of Eastern rulers, including Turkish and Persian turbans and the Muscovite crown. This was indicative of the Pope’s desire to usurp the powers of secular rulers as his own.

Sarpi also drew attention to the use of the title ‘Vicedeo’ (Vice-God), which seemed to place the Pope on a level with God himself. Protestants like Duplessis-Mornay were willing to go even further. At the bottom of the print, we find another note in French, explaining that the inscription was a providential sign of the Pope’s blasphemy (if perhaps, to modern eyes, a rather tenuous one…). The reasoning was this: if you take the title ‘PAVLO V VICEDEO’ and add up the Roman numerals which feature (V[5] + L[50] + V[5] + V[5] + I[1] + C[100] + D[500]), what do you get? It’s the apocalyptic number of the beast, 666. Here was proof, positive that the Pope was indeed the Antichrist, the ultimate enemy of the one true Christian church.

Did Duplessis-Mornay reprint the image exactly as printed in Rome? It is hard to say. Though Sarpi expressed hopes of sending copies to Paris, no known versions that can be proven to have been printed in Rome survive. There were reports at the time that the Pope had ordered all copies to be destroyed, aware the print went too far. Equally, it is possible the print was a fabrication by the Pope’s enemies all along. Minor discrepancies between Sarpi’s description and Duplessis-Mornay’s print suggest that it is most likely a Protestant reimagining (and re-engraving), inspired by Sarpi’s words.

And yet, if it was an invention, or a Protestant exaggeration, it is notable how closely the creator of the print stuck to genuine features of papal propaganda from the time. The title ‘vicedeo’ was deployed by supporters of the Pope on other occasions, such as in a pamphlet printed in Bologna in 1608. The author, Benedictus a Benedictis, opened his dedicatory letter to the Pope with the bold address ‘Monarcha & Supremo Vicedeo’. News and copies of this work were circulated widely, and survive in both Protestant and Catholic archives.

The imagery the print draws on to glorify the Pope also mirrors genuine Catholic productions of the period. The four female allegorical figures flanking the Pope are clearly meant to represent the four regions of the globe: Africa sits on an elephant and holds a sheaf of wheat; a crowned Europe sits on a horse, carrying a horn of plenty; a bare-chested America, wearing a feathered headdress and wielding a bow and arrow, sits with a severed head pieced by an arrow at her feet; and a richly robed Asia, seated on a camel, holds flowers and swings burning incense. The choice of symbolic objects exactly matches details found in Cesare Ripa’s Iconologica; a book of iconography printed in its first illustrated edition at Rome in 1603. In the years that followed, Ripa’s allegorical models for the four regions of the world were deployed with increasing frequency in papal propaganda, as Rome made ever bolder claims for Catholicism’s global dominance. If Duplessis-Mornay’s print was a Protestant fabrication, it was a careful one, which exploited and subverted known features of papal writing and imagery: Catholic propagandists were hoist by their own petard.

In the age of AI image generation, this sort of manipulation of images of powerful figures has the power to be even more persuasive and damaging. Indeed, the current pope has already fallen victim: a fake image of Francis, apparently sporting a white Balenciaga puffer jacket (retail value c. £3,000), did the rounds on social media in 2023, to the delight of his critics.

The distribution of Duplessis-Mornay’s papal portrait provides a case study in the radical uncontrollability of printed material. There were, of course, efforts at restraint, such as the system of print licensing in England or the Index of Prohibited books in Rome. But it was increasingly recognised that shutting down print dissemination entirely would not work. Instead, writers attempted to fight back, penning refutations.

In such works, portions of the enemy’s arguments would be reprinted then immediately refuted. A comparison might be drawn to efforts to ‘fact-check’ political debate today. Yet, as with modern fact-checking, readers sympathetic to the view being refuted often complained that such refutations had truncated and misrepresented the original argument, missing the fundamental point. Thus, people observing these debates often became only further entrenched in their own views. The English Catholic convert Benjamin Carrier (1566-1614), for instance, claimed that a major factor in his conversion was the disparity between the version of Catholicism presented in fiery Protestant polemics, and that described by Catholics in person.

We see the same phenomenon today when a gap emerges between opinion on Twitter and broader public opinion. Imagine the author of a viral tweet, convinced that she has authored a zinger, which will undermine an opponent’s argument at its foundation. A few thousand likes and retweets of agreement later, and her sense of vindication only grows. But in all likelihood, a large proportion of those who silently view the tweet – without responding – remain unconvinced. To them, the supposed zinger reflects no genuine engagement; it’s merely a poor argument that misses the point of their stance. The only effect has been to reinforce pre-existing views.

In his Novum Organum of 1620, Sir Francis Bacon listed the printing press, alongside gunpowder and the nautical compass, as one of three inventions that had ‘altered the face and state of the world’. Few would deny the internet a place on a list updated to reflect the last half century. Both these communications revolutions set in motion dramatic and wide-ranging societal shifts, giving observers cause for celebration, alarm and – most fundamentally – confusion.

Amid the chaos, is there anything we can learn from the sheer messiness that followed the print revolution? The ‘market of ideas’ that print created was far from ideal, and we should be suspicious of rose-tinted claims to the contrary. Though communication revolutions allow a broader range of people to feel like they can influence and direct political discourse, the truth is that acceleration catches everyone out.

In the end, what sold in the age of the pamphlet were truncated, extreme arguments. These were often attacks on opponents that relied on distortion. Consequently, such attacks often did more to galvanise existing supporters than persuade opponents, who saw a caricature rather than real understanding of their position. The 17th century was a period of bitter confessional division, which was aggravated rather than ameliorated by the expansion of printed debate.

Similarly, we have good reason to be wary about the faster, broader-based market of ideas that has been created by the internet and social media today. Like our early-modern predecessors, we are experiencing a period of adjustment and uncertainty. We, too, are having to adapt to political debate conducted at ever higher speed, which abridges arguments, and is beamed to many audiences at once. In many ways, these are changes which endanger and impoverish political discussion.

Alas, like the early moderns, we will have to get used to it. The face of the world has been altered again, in such a manner that no corrective surgery can reverse. There is no turning back, but we can proceed with caution. We should diagnose and spread awareness of potential problems, paying close attention to the manifold specific contexts and audiences that shape – and distort – political discussion. And we must do all we can to cling on to slower, calmer forms of intellectual exchange, even though they are not always the most marketable. Scrupulously argued doorstopper books and long evenings of debate in the pub: these are forums to cherish and protect.