Pornography, Life 2.0 and the citizens of a quaint New Mexico town were just some of the subjects invoked during "The Great Debate: What is Life?" a panel presentation featuring preeminent scientists, held on the campus of Arizona State University (A.S.U.) in Tempe, Ariz., on Saturday, February 12.

Emceed by Lawrence Krauss, A.S.U. Foundation Professor, astrophysicist, author, and director of the noted A.S.U. Origins Project, the evening was dedicated to stimulating discussion on some of the simplest, most mundane questions ever posed: what is life, where and when did life originate, how can we search for its origins, and can we produce life in the lab. Truly boring stuff. Frankly, why the sold-out audience of over 2600 (who paid to attend, mind you) didn’t walk out, is mystifying.

But with Krauss and Roger Bingham, Director of The Science Network and cognition professor at the University of California, San Diego, at the helm of an all-star panel featuring evolutionary biologist Richard Dawkins, NASA planetary scientist Chris McKay, A.S.U. physicist and author Paul Davies, biologist and entrepreneur J. Craig Venter, and Nobel Laureates Sidney Altman and Lee Hartwell, there was at least some entertainment value to the event. And a few scientific surprises and sociological spectacles poked through as well, for folks who like that kind of stuff.

Life, it turns out, is not so easy to define. Although the panel agreed that the characteristics of what we currently refer to as living organisms include reproduction/replication with the ability to pass on one’s own genetic code, and metabolism, there was still debate. Krauss crystallized the wrangle by conjuring the famous quote by Judge Potter Stewart regarding porn. "At the heart of what Origins is about is the question what is life," relayed Krauss. "Every time I think about that I think about pornography. Like the Judge said, ‘I can’t define it but I know it when I see it.’"

So after hundreds of millions of years of life existing on our blue sphere, and thousands of years of philomaths dismantling the question of our genesis, we still are not sure where or from whence we came. But at least we know, for now, that the rock idling by that cactus is not a living being.

Or is it? Davies, who chairs SETI’s "welcome committee" (if and when creatures from other planets decide to pay us a visit), is dedicated to finding Life 2.0, and he’s betting that it’s on Earth. Life 2.0, part of which he refers to as a Shadow Biosphere, is any life that cannot be traced to the Darwinian Tree of Life, from which all known organisms have sprung. If we’re gonna discover Life 2.0, Davies recommends three courses of action – look in locations that are beyond the current span of life (like extreme places such as deep-ocean vents), design experiments that filter for current life, and make an educated guess as to how Life 2.0 would differ. Using these three qualifiers, Davies is convinced that Life, not as we know it, and if it does indeed exist here, will be found within 10 years.

The significance of finding life elsewhere, either on our world or another, was not lost on McKay, who is involved in the next Mars mission. Even one other type of "alien" life, i.e. a non-derivative of the Tree of Life, "means that life is common in the Universe and is no longer the private knowledge of residents of Roswell, NM," he argued, to the chuckles of the masses.

Later, Davies echoed this sentiment. "If we can find a second sample of life, and it doesn’t matter whether its on Earth or Mars, it will means the Universe is teeming with life," he said. "Are we alone in the Universe? Just by finding Life 2.0 we will answer this question and the easiest place to look is right under our noses. This affects every human being now. It is not just a question of what happened so long ago."

The Great Debate was the public face of a weekend-long private workshop Krauss hosted for the panelists and other scientists from such diverse fields as geology, astrophysics, and biochemistry. Participants agreed that although there was nothing earth-shattering that announced, either at the workshop or the public affair, the opportunity engendered deeper discussion regarding origins of life, especially since there is much more now known about the biochemistry of the early Earth and the possibilities that the so-called RNA World may hold as a precursor to Life 1.0.

"10 years ago, getting to the Beginning [of our origins] was extremely difficult," Krauss stated to me. "But now with developments in chemistry and biology, the idea that in 10 years we could understand life and create it in a lab…as a cosmologist, that would be like creating the Big Bang in a lab."

This private statement certainly paralleled Krauss’s opening remarks at the Great Debate, in which he conjectured that "it may be to truly understand life we need to create it", flashing a picture of Frankenstein’s monster on the screen, and half-joking that fairly soon, Venter may actually develop his own game to create life.

Later, Krauss elucidated his opinion about building life to comprehend it: "We’re on the threshold of synthetic biology, of trying to create life and we still don’t know the minimum requirements of the biological structures," he told me. "It’s like understanding a car – you have to take it apart and put it back together again." Now that’s a sexy thought.

Alaina G. Levine is a science writer based in Tucson, AZ.

The views expressed are those of the author and are not necessarily those of Scientific American.