Flying west 15 hours I never saw the sun set, but in the evening, between the skyscrapers of Tokyo, I glimpsed the full moon I’d left the night before shimmering on the Potomac, the same full moon beaming down over China, Myanmar, and Vietnam. I found myself contemplating whether the writers in prison in those countries could also glimpse the luminous golden light from a corner of their prison cells. I was in Tokyo for PEN International’s 76th Congress.

Writers from 90 centers of PEN gathered to discuss “The Environment and Literature—What can words do?” and to commemorate the 50th Anniversary of PEN’s Writers in Prison Committee, that particular group of writers who advocate on behalf of colleagues imprisoned, threatened or killed for the expression of their ideas.

In its history, PEN International’s Writers in Prison Committee has been instrumental in getting the releases of such well known writers as Arthur Koestler, Wole Soyinka, Vaclav Havel as well as thousands of others in countries on every continent and from every political condition, from fascist regimes, communist regimes, marginal and faux democracies, wherever words were considered subversive and powerful enough to threaten. At the moment the most cases and the longest prison sentences for writers are in China, Myanmar, Vietnam and Iran, but writers are under threat in over 60 countries with the internet offering a new frontier for protection of free expression.

At the keynote ceremony of the PEN International Congress a play, Water Letters by Hisashi Inoue, dramatized the theme of the earth’s and mankind’s connectedness, especially through water. Human beings are largely made of water, and water—rivers, streams, oceans—links us all, the characters intoned. If the source of water is threatened in one area, there are repercussions in another. There is one earth, one people; the environment is in our hands.

The same can be said of freedom of expression. The 11-year imprisonment of Liu Xiaobo for urging democratic reform in China not only imprisons the man but the possibility of his next ideas. The imprisonment of writers in Myanmar and Vietnam, the more than 60 imprisoned writers, journalists, and bloggers in Iran affect the flow of ideas worldwide. The more than 50 journalists killed in Mexico chills freedom and undermines the rule of law beyond Mexico’s borders.

Yet ideas, like water, have a way of flowing around barriers and through bars and seep into the stream of thought if passed from one person to the other. And so writers outside prison pass on the work and writing of their colleagues.

Looking up at the moon, we contemplate the universe from the same point of focus and glimpse for a moment our connectedness.