The seventeenth-century English philosopher Thomas Hobbes thought speech to be the most useful of all human artefacts, writing in Leviathan in 1651 that

The most noble and profitable invention… was that of Speech… whereby men register their Thoughts… and declare them to one another for mutuall utility and conversation; without which, there had been amongst men, neither Common-wealth, nor Society, nor Contract, nor Peace, no more than amongst Lyons, Bears, and Wolves.

Writing during the English Civil War, Hobbes placed a large portion of blame for the breakdown of order on firebrand orators and ‘schoolmen’ who stoked sedition among the populace. Yet however fraught with abuses and misunderstandings, communication through words is the main means we have of acknowledging each other’s humanity and our need to share the world with people we disagree with. How, then, to communicate safely when governments monitor free speech and see it as a mortal threat?

One of history’s great champions of freedom – who often got into deep trouble for speaking his mind – spent years grappling with this question. Under torture for suspected involvement in a plot against Florence’s Medici leaders, Niccolò Machiavelli’s inquisitors read out disrespectful words he’d been overheard using and demanded, ‘Did you say these things or not?’ He confessed that he had.

Machiavelli hadn’t realised that it was a crime to criticise rulers, even in private. The Medici had started penalising their free-speaking critics when they returned from long exile a few months before Machiavelli was tortured, effectively turning the Florentine Republic into a family princedom. ‘The truth often makes war on him who tells it,’ he wrote in ’The Ass’, a poem that shows how easily tyranny can turn humans into beasts who grunt whatever nonsense helps them blend in with the herd. ‘Princes,’ he notes in his Discourses on Livy, ‘are always spoken of with a thousand fears and a thousand hesitations.’

Yet Machiavelli refused to stop speaking of princes and all sorts of repression. He invented creative ways to get around constraints, telling a friend that when he writes about the Medici in his Florentine Histories ‘I shall try to do my best to arrange it so that – still telling the truth – no one will have anything to complain about.’

Machiavelli drew inspiration from Plutarch, a Greek who lived under the Roman Empire. When the Caesars turned the republic into a tyranny, it became as dangerous to speak freely about princes or independence for Rome’s conquered provinces as it is in today’s Russia, Turkey, and many other countries around the world. Instead of silence or outright rebellion, Plutarch suggested a range of diplomatic, even friendly, ways to engage with one’s oppressors – though he could not, of course, openly call the Empire oppressive.

Defending the old Greek ideal of parrhesia – frank speech – he urged speakers to take great care about how they express their views. Avoid haranguing or preaching, he argued, which irritate people and insult their pride. Show tactful consideration for your audience. Avoid immoderate liberty of speech. And admit that you and your fellow-thinkers might get some things wrong, just as Plutarch’s hero Socrates admitted his ignorance even when talking to people of tyrannical spirit.

But even if one strives to follow this ancient advice, the challenges are hard to fathom in today’s world where freedoms of speech and inquiry face many new threats. Academics like me are often asked to speak about democracy, national identity, or feminism in countries where these are ‘sensitive’ topics.

Though we want to keep engaging colleagues and students in those countries in ideally open, borderless conversations, however, we would be irresponsible not to ask hard questions. If we agree to speak in settings where speech is monitored, how careful will I have to be in my choice of words, in the way I frame my arguments? What if something I inadvertently say should end up causing trouble for my hosts? And whatever I say now, if it is recorded or put in a podcast, how can anyone foresee what might be branded subversive next month, or in a year? Moreover, there is a new threat to free speech unknown to earlier ages – the internet mob, often encouraged by regimes that seek to silence critics.

People facing these dilemmas might do well to combine Machiavelli’s fox with his lion. Lions are bold fighters but take stupid risks; the fox, he says, is more circumspect, good at avoiding snares. To keep talking is the courage of the lion; to do it with circumspection is the way of the fox. Machiavelli, Plutarch, and Socrates urged people to keep talking in conditions of oppression. Never give up hope, they said, that tyrants can be persuaded to give up tyranny – as Socrates’ friend Plato tried to persuade Syracuse’s tyrant Dionysius to do, and Machiavelli the Medici – albeit in diplomatic, indirect ways.

Above all, never abandon fellow writers, philosophers, scholars, or lovers of freedom anywhere. As long as there’s a chance to keep talking, do it, even if you have to exercise diplomacy. The key thing is to exemplify – not preach – ways of talking that make conversation partners value their own free minds and respect those of others. That, after all, is good practice even when there is freedom of speech – and that freedom can be infectious.