The role of the public intellectual is a hot topic at present, according to a debate at this week's British Sociological Association conference at the University of East London.
Yet academics seem unable to agree precisely on what public intellectuals contribute and who listens to them.
One key area of debate is whether they are extinct or alive and well.
Jeremy Jennings, professor of political theory at Queen Mary, University of London, said: "There is clearly a sense that the role of the public intellectual is changing - or might, in fact, have ended."
His views have been backed in recent years by articles and publications lamenting the demise or absence of public intellectuals.
Professor Jennings said: "I would say that the public intellectual has gone - it is all rock stars and film stars and the culture of celebrity these days. If you want to organise a public outcry, you don't get Pinter or Hobsbawm, you get Bono or Bob Geldof."
Others argue that there is little evidence of this. Iram Siraj, professor of early childhood education at the Institute of Education, believes the past decade has seen a dramatic rise in academic engagement in public life.
"There is constantly a desire to engage with policy colleagues and the media and engage with public life in a range of ways," she said.
Marcus du Sautoy, professor of mathematics at Oxford University and holder of a media fellowship from the Engineering and Physical Sciences Research Council, said: "Research councils are recognising that we need ambassadors to persuade people of the importance of science.
"I get a lot of support for the effort I put in trying to connect science to society."
Academics also debate what constitutes an intellectual, public or otherwise, drawing a distinction between those who speak within their area of expertise and those who comment more widely.
Professor Jennings said: "The intellectual is someone whose authority comes from being an expert in a particular field, and who uses that to speak out about general issues of social concern.
"I would say that is the distinction between the intellectual and the academic."
Frank Furedi, professor of sociology at Kent University and author of Where Have All the Intellectuals Gone? , argued that public intellectuals needed expertise in one area. He said: "Academics as intellectual authorities should use that cultural capital to analyse everyday problems and give a clear viewpoint on them.
"Academics are discouraged from doing that. Some do not see it as worthy, some see it as beneath them to talk to the public in the language of everyday life."
Donna Dickenson, emeritus professor of medical ethics and humanities, University of London, who was awarded the Spinoza Lens Award in 2006 for commitment to public debate on ethics, said the UK media needed to give more space to intellectual debate.
"There are some very prominent public intellectuals: Richard Dawkins, Robert Winston and Germaine Greer," she said. "But the media tended to present debates as pro and against, black and white, and create 'media stars' who are comfortable with this and with the soundbite."
Andreas Hess, senior lecturer in sociology at University College Dublin, believes it may be growing harder for academics to engage with the public due in part to increased specialisation within academe.
But he said intellectual engagement was essential. "I always thought of participating in the public realm outside academia as a great challenge and opportunity," he said.