You could say Margaret Somerville's latest book, The Ethical Imagination: Journeys of the Human Spirit (House of Anansi Press, $18.95), began when the ethicist found herself staring vindication in the face.

“I was starting to collect all these other ways we could think about things,” says the founding director of the Centre for Medicine, Ethics and Law at McGill University, on the line from her office. “Not think about them, actually; know without really doing reason. And one day I was walking through the airport and I saw this book called The Unconscious Civilization. It was John Ralston Saul's [1995] Massey Lecture. I picked it up and I started to read it, and I thought ‘Oh my God, this is what I'm doing.' ”

Ralston Saul's work—about challenging how we negotiate democracy—was only affirmation, though, for a line of thought that the widely read and travelled Somerville had begun decades earlier in Australia.

At the age of 11, Somerville won an all- sciences scholarship. “It was a revelation to me when I found out there was such a thing as history,” she says ruefully. She went on to various careers: she taught agricultural science at a boy's school, got degrees in pharmacy and law, worked as an antique dealer and a lawyer, then ended up with a doctorate in medical law.

The engaging Somerville has taught ethics at McGill for 30 years, in that time refining the thoughts that compose both her 2006 Massey Lecture and The Ethical Imagination: that there are multiple ways of knowing, that our fear of uncertainty has built a culture of anxiety, that compassion and a sense of the sacred are missing from our central values, and that inaction and materialism will pervert our greatest asset: hope.

Somerville values science for helping us understand our place in the cosmos, yet cautions we are more than empiricism. “We're the wondrous outcome of the combination of stardust and time,” she says. “Once you have kind of contemplated and felt that, then you think ‘We can undo that in a nanosecond with these new technologies. Then how much more awe and wonder and respect and caution we should have before we do that.' I don't want to tell people what to do. I do want to try to tell people, ‘Make sure that you're understanding the enormity and the extraordinariness of what you're doing.' ” It's that validation of the nonscientific that has given rise to friction among her colleagues. She relates: “Someone said to me, ‘You know, Margaret, you're dangerously on the edge of total bullshit.' ”

Another group upset with Somerville has focused on her stance against gay marriage. (She's in favour of same-sex civil unions but not gay marriage, since marriage exists to procreate.) “There are good arguments on both sides,” she allows. “The good argument on the same-sex side is that gay people have been horribly discriminated against. They still are in some places, and we've got to stop that. It's absolutely appalling. But the good argument on the other side is that kids need a mother and a father, that they want to know who their own biological parents are, and everything we're learning is they're best off in that family.

“Somebody told me the other day,” she continues, “that I'm the gay community's worst nightmare. It's pretty hard to argue against somebody who says, ‘Look, I'm for gay rights, but I also care about kids.' What are you going to say? ‘I don't care about kids?' All that's left is that they've got to label me as a bad person and dismiss me.”

What we need more than mudslinging is a commonality. But where will we find it? “Some people will find it in very orthodox religion,” she says. “Some will find it in more evangelical religion, some will find it in tradition, some will find it in spirituality, some will find it in what one of my colleagues calls secular religion—like the Olympics, or sport. That's one of the tragedies when something that should be able to carry those kinds of feelings and experiences becomes, let's put it bluntly, corrupt.”

She laughs. “All I try to do is try to be real. And sometimes I succeed. And sometimes I get into trouble.”

Margaret Somerville delivers the third of the Massey Lectures on Tuesday (October 17) at the Chan Centre for the Performing Arts. For tickets, visit Ticketmaster.ca. The lectures will be broadcast on CBC Radio One's Ideas from November 6 to 10.