I’m looking at a picture of the Great Wall of China. It’s on a calendar given to me by my friend and acupuncturist Wenbo Xu. There are two crane-like birds in a meadow in the foreground. Beyond them the wall uncoils along a succession of steep wooded ridges towards distant mountains. It divides the landscape in two.

Yesterday it was our Edinburgh International Book Festival board Christmas lunch. We all know each other well and it’s always a jolly affair which culminates in us taking turns to name our favourite book of the year. The list is later circulated. Bearing in mind that we have literary editors, publishers and literary agents round the table (former Man Booker Prize judges among them), it’s usually a pretty good list.

Yesterday one person nominated The Examined Life by the psychoanalyst Stephen Grosz. I happened to be at his event last summer, sitting two rows behind Ed Miliband who had dropped into Charlotte Square as all sensible visiting politicians now do when they come to Edinburgh in August.

Stephen Grosz spoke quietly and movingly about the patients whose stories he tells in the book. At one point he quoted Simone Weil, who wrote that every separation is also a link. She illustrated this with the image of the prisoners who learn to communicate by tapping out their messages on the walls of the cells that keep them apart.

My picture of the Great Wall makes me think of that. It makes me think that even the conflicting desires of those beyond the pale to enter the forbidden land and those within to keep them out, are preferable to indifference and silence; that both sides are imprisoned by their ideas and feelings, and that even as a symbol of enmity the wall is still, at least, serving to conduct human feeling.

In the case of Weil’s prisoners, of course, if you tap away long enough the wall might even come down. Our job as a book festival is to allow people to see that those separations – of political, religious, social, economic, cultural ideas – can also be links, that they bind people together in the common human experience of having passions and that that, paradoxically, can also be the route to accord.

As well as being the centenary of the outbreak of World War I, 2014 is the year in which Scotland will host the Commonwealth Games and go to the polls over Independence, three topics which come laden with potentially divisive feeling. Our job at the book festival will be to demonstrate that in real dialogue – as opposed to the bear-pit atmosphere of most current public debate – there must be the potential for understanding, for literally ‘standing under’ the person of opposing views and experiencing the world through their eyes. The alternative is a simple trading of insults across the wall.

It won’t necessarily be easy but the thought that what separates us can also join us will help. It’s certainly true of language. In my daily work I’m constantly conscious of the wall erected by language – the language of officialdom, of technology, of professional cliques. My job is to help those people imprisoned on either side of it to start tapping away in the hope that the wall will gradually become more porous and may eventually melt away, becoming a river in which thoughts and feelings can run together. Language as a river into which we can all flow seems like a sustaining thought for 2014.

On a less serious note, the calendar also tells me that I am an Ox, a symbol I share with my grand-daughter, Zoë. It tells us we are ‘Inspiring, bright and patient, but egoistic. Can be happy even by yourself. Wed a Snake or Rooster and make an outstanding parent. Sheep will bring troubles.’ I married a Dragon, with no obvious ill-effects. At four, Zoë is a little young for that kind of thing.