John Banville has hit out an increasing intolerance which is threatening to destroy free speech and open debate, and he warns "we are living through a very dangerous time".
The Booker Prize-winning author described how he "shivers" when he hears "publishers being coerced into cancelling publication of what are deemed to be unacceptable opinions" and says it isn't a long step "from suppressing books to burning them".
The novelist was speaking after becoming the only Irish name among 150 leading writers, activists and academics to sign an open letter denouncing the "restriction of debate".
The letter, published last Tuesday in Harper's Magazine, denounces "a vogue for public shaming and ostracism" and "a blinding moral certainty". Signatories include JK Rowling, Salman Rushdie and Margaret Atwood.
Speaking to the Sunday Independent, Banville said: "I hope it will encourage at least some people to pause and reflect. Humankind seems to need periods of extremism bordering on senselessness, who knows why."
But he says he will not kowtow to the mob: "I would never dream of censoring myself - what writer with any self-respect would?
"What is particularly worrying in the current climate is the cravenness and cowardice of people in positions of authority who should know better than to heed the demands of the mob.
"A mob is a mob, even when its aims are benign - the end cannot be allowed to seem to justify the means."
In recent months, a number of figures have been shamed online for making comments considered offensive by some, including on issues of gender, race, and sexuality. In June, the New York Times opinion editor bowed to calls for his resignation after he published a piece by a Republican senator calling for military forces to be sent to cities where anti-racism protests had turned violent.
The same month, Rowling came under fire for her beliefs on the trans community. Harry Potter fan sites called for cancelling the brand over her views. 'Cancelling' means an individual who has spoken in a controversial manner is boycotted. It can be brought about by 'offence archaeology', when long-forgotten offensive comments or unorthodox views are uncovered.
On the current climate, Banville asks: "Who decides if this or that opinion, joke or political action is 'unacceptable'? Who are the self-appointed arbiters, and by what right do they judge?
"I heard Barack Obama the other day talking sense when he observed that it is easy, and gratifying, to point the finger at some person or group whose views you disagree with and then congratulate yourself on your courage and effectiveness. I saw this in the 1960s, when we thought we only had to shout a few slogans and go on a few marches and the world would change."
But he says: "Change is brought about slowly and with much effort and care, as Martin Luther King, among others, well knew."
Irish novelist John Boyne has tweeted in support of the letter, writing "hounding people for perceived moral slip-ups" is the "opposite of free speech".