What's the Dalai Lama's secret? He's got over two million Twitter followers, people buy his books in droves, his speeches sell out stadiums. In a highly cynical age, he's held the public's attention for over two decades with some pretty elementary ideas: the essence of human nature is to be happy, human beings are happiest when they help others attain happiness, all major religions nurture the most basic ingredient of happiness, namely compassion, but you don't have to be religious to be compassionate, you just have to live up to the basic goodness of your human nature. Like Socrates saying "I know that I know nothing", it's not just the simplicity of the message that attracts people, it's the remarkable journey of the man who is articulating it. The story of his escape from Tibet into India, his successful establishment of a government in exile, his continual advocacy for peaceful negotiations with his Chinese occupiers even while the culture and lives of his people are crushed day after day -- these things are well known, and more than enough to command admiration and attention. But what is astounding about the Dalai Lama is how much more he is than the spiritual, symbolic and political (although he's stepping down from that role) leader of the Tibetan people. For those of us who believe religion is a source of inspiration and a bridge of cooperation, at a time when people presenting religion as a bomb of destruction are ruling the airwaves, the Dalai Lama is our single most powerful example. It is this part of his mission -- Dalai Lama as interfaith leader, which is also the subject of his most recent book, "Towards a True Kinship of Faiths: How the World's Religions Can Come Together" -- that has brought him to Chicago for a set of presentations sponsored by the Theosophical Society. Like much of what the Dalai Lama does, the book and his presentations have been deceptively simple. He states clearly that inter-religious cooperation has to be one of the central priorities for our world, and says that it is one of his three core missions in life, along with promoting the basic human values of compassion and happiness, and finding a solution to the crisis of Tibet. In the beginning of the book, the Dalai Lama tells stories of his personal encounters with different religious leaders and uses them to highlight the history of positive encounters between different religions. We find out about his conversation with the Trappist monk Thomas Merton, who came to visit him in Dharamsalla only a few weeks before he died. The two monks compared their robes, the times they each awoke for meditation (2:30 and 3:30 am, respectively, the Western tradition being the more severe on this particular count), the spiritual dimensions religious ritual was meant to awaken. It is the perfect personal story to lead into a brief history of the Christian presence in Tibet, which began as early as the 17th century, and included an Italian Jesuit priest who wrote a lengthy text in Tibetan that the Dalai Lama cites as an important document of early Tibetan Buddhist-Catholic interfaith dialogue. The rest of the book includes chapters on major world religions, in which the Dalai Lama essentially explains what he admires about Christianity, Judaism, Islam, Hinduism and other faiths. He writes of the beauty of the Muslim call to prayer, the remarkable continuity of Judaism even in exile, Jesus as a symbol of service and love. There is a chapter on compassion, unsurprising as that is probably the term that His Holiness is most associated with, outside of perhaps 'Tibet' and 'Buddhism'. What is surprising is that the Dalai Lama writes about what he has learned from other religions about compassion. It reminded me of how King viewed Gandhi -- as someone from another religion who gave him a broader idea about values within his own. Over the past decade or so, enough research has been done on religious diversity and interfaith cooperation to constitute the beginnings of a science of the field. Here's what we know from Robert Putnam and David Cambell's "American Grace": positive personal contact with people from different faiths significantly improves people's attitudes towards those religions and communities. Here's what we know from work done by Stephen Prothero and Pew and Gallup surveys: appreciative knowledge of other religions improves people's attitudes towards those communities and traditions. In other words there is a strong relationship between attitudes, behaviors, and knowledge -- a magic triangle, so to speak. And that is precisely how the Dalai Lama has shaped his book and his recent teachings. Get to know people from other religions personally, preferably by doing service work together. And get to know some things you admire about their traditions, especially those areas that have commonality with your own. A good place to start is on the shared value of compassion. In his simple and straightforward way, the Dalai Lama is telling stories that work the triangle. To say there is a science to interfaith cooperation is not to deny that there is also an art. And it is his mastery of that art -- that infectious smile, his way of making stadiums feel like intimate environments during his teachings, the quality that makes millions of people think 'I believe him' when they hear the Dalai Lama speak -- that makes His Holiness the most important interfaith leader in the world. I suppose one could say that he preached to the choir in Chicago. But if the choir learns the song of interfaith cooperation that the Dalai Lama is teaching, and dares to sing it out loud in the face of the haters and the extremists, and if a few of those choir members become preachers of this song themselves, then we join the Dalai Lama on his mission to make interfaith cooperation a 21st century reality, and we have a share in the secret of his success, perhaps even his happiness.