I stopped at a red light in a northern Minnesota town. I was in the right lane and glanced at the driver to my left — an elderly man with the classic, direct-from-central-casting face of a Hollywood grandfather. The gray mane and life lines (not wrinkles) were wrought and balanced to signify wisdom, cheerful stoicism and an endearing patriarchal gruffness that always twinkles. I imagined him balancing adoring toddlers on each knee; capturing the grudging reverence of teenagers; winning the trust of all women. My glance turned into a covert study, and it crossed my mind the man should be scouring Beverly Hills for an agent.

The light turned green and Kindly Grandpa (so my mind had branded him) accelerated. His rear bumper eased into view, and I saw a bright yellow sticker with black letters that read: PEOPLE SUCK.

I guffawed. So much for first impressions. I wondered what Kindly Grandpa would think about the following news:

In January, Reuters reported that an international team of researchers produced a paper arguing that our planet has entered a new geological epoch, the Anthropocene ("human epoch"), ending the Holocene, which began after the last ice age about 12,000 years ago. The impact of our numbers and activity on the Earth shows, said Colin Waters, the team's leader: "We are becoming a geological agent in ourselves."

Especially since 1950, population growth and technological innovation have ushered in a new age. Our influence includes human infrastructure that covers vast tracts of the world's surface; a doubling of nitrogen and phosphorus in the soil from agricultural additives; radioactivity from atomic weapons tests in ice and sediment that will be detectable for 10,000 centuries, and carbon dioxide concentrations in the atmosphere that have doubled since the start of the Industrial Revolution and have steeply accelerated the past 75 years.

With the possible exception of the nuclear explosions, none of it is all virtuous or all evil. As mammals in the biosphere, we can't be faulted for reproduction — it's what the living do, whether they are bacteria or people, the most complex of the multicellular life forms known as "metazoans."

Once we multiplied into the billions, the primary need to provide food, clothing, shelter and tools led to our dominance of the planet, inducing the extinction of many species unable to withstand the swelling human tide. This is not unprecedented. About 2 billion years ago, a massive proliferation of cyanobacteria renovated the atmosphere so profoundly that most other life forms perished in probably the greatest mass extinction in history. The "poison" they released was oxygen, thus setting the stage for our evolution, and demonstrating that the biosphere is either neutral or perverse, depending upon your point of view.

My view is that the cosmos is perversely fair: No favorites are chosen or are even possible. So far as we can tell, the house rules don't specially accommodate microbes, people or anything else. From the human perspective, what matters most is the values we assign to what is and what happens.

For example, as a firefighter, I understand fire is a physical/chemical/biological phenomenon that always follows the rules. A wildland fire ignited by lightning is often viewed as a beneficial process fostering ecological renewal — a "good" fire. If, however, your house is aflame, that is a "bad" fire.

Since the human race is clearly a potent natural process, as ubiquitous as fire, and people have the ability to think about that, is there a best way for us to consider ourselves? I notice three basic outlooks.

One is the Open Society Triumphant (OST). Some champions of this view are physicist Freeman Dyson, philosopher Karl Popper, physicist David Deutsch, novelists Arthur C. Clarke and Ayn Rand, and Rand's fictional character John Galt. Though none of these would likely posit a "purpose to evolution," the basic notion is that humanity is the de facto master of the biosphere, that we will continue to alter it and ourselves, and that these transformations are ultimately positive, speaking to our "open" future.

The extinction of other beings and our impact on the atmosphere, oceans, soil, etc., will be managed by technological and biotechnological means, and though our success and survival are not guaranteed, they are probable. We just need to keep on doing what we're doing, only more so. The OST camp celebrates the Anthropocene's arrival and anticipates its diffusion into the solar system and galaxy.

A second outlook is Gaia's Important Footnote (GIF) — Gaia being a personification of the biosphere. Some proponents of this view are teacher and farmer Wendell Berry, scientist and activist Aldo Leopold, polymath and polemicist Ivan Illich, novelists Margaret Atwood and Edward Abbey, and Abbey's fictional character George Washington Hayduke. GIF acknowledges that humans are in some ways singular, but we can't trump the ecological/cosmological imperatives, and it's possible for us to overextend. We cannot, for example, destroy the planet, but we can alter it so rapidly and radically that the conditions for our survival disappear — think cyanobacteria.

As with the OST, our success and survival is not guaranteed, but GIF says we'll probably fail unless we soon make significant changes that more closely align with existing ecology, and that purely technological "fixes" are pie-in-the-sky and/or dangerous hubris.

A third outlook is one that most people are raised with in one version or another: We are the product of a creator deity with a vested interest in our fate, and this deity has the will to intervene, that is, to change the rules. A deep faith in this outlook — regardless of particular religion — is mostly incompatible with the other two, which are science-based as opposed to belief-based. Despite continuing sound and fury at the local level, this third outlook has had minimal influence on the general human trajectory for the past two centuries and will likely continue to wane.

At root, OST and GIF are opposed. For example, OST views exponential human population growth as an inevitable, almost preordained, asset — more human brains and experience to help figure it all out. GIF considers our population expansion as at best a loose cannon, and at worst a kind of ecological weapon of mass destruction.

So, are we queens or pawns? Are we headed for the stars or the fossil beds? Neither? Both?

As with most people, I find merit in both OST and GIF, but struggle. For example, I'd harbor less grief at the prospect of human extinction if it weren't certain that domestic dogs would exit with us. Most of us are salved or lulled by the daily duties of living: It is not "I think, therefore I am" but rather "I mow the lawn, therefore I am." Nevertheless, we all have an impact, and if we wish to be conscious, deliberate players on the world rostrum, how we act needs to be informed by some brand of philosophy.

In a recent special issue of National Geographic magazine, David Quammen wrote about the past, present and future of Yellowstone National Park and the surrounding territory. One focus of the article was the condition of three keystone species: bison, wolves and, most notably, grizzly bears. The harsh human colonization of the past century and a half has forced these animals to scramble for survival. After listing what people could do to help protect them and the greater Yellowstone ecosystem — none of it easy — Quammen notes, "But if the Yellowstone grizzly bear is expected to adapt, modify its behavior, and cope with new realities, shouldn't we be expected to do that too?"

The GIF outlook would shout, "Yes!" The OST outlook would be ambivalent, with some even saying, "Save the grizzlies? They're doomed — get over it! There's a better world to come."

Whether anyone actually changes their behavior — willingly or unwillingly — is a separate issue, but it seems to me that not enough humans have consciously considered where they stand on the question of human destiny. In past eras, this responsibility defaulted to the third outlook, to priests and gods, and "ordinary" people focused on the chores of getting by. That is not sufficient. Especially in the energy-intensive developed world, the effect of getting by is too momentous to be accomplished mindlessly.

Both OST and GIF support a unique calling for we human animals. You can be a lump of protoplasm if you wish, aimlessly bobbing in the backwash of history, logging time between your unbidden birth and inevitable death, ceding responsibility to others. Or you can think and act from earned convictions and observations about what it means to be one of the 7-billion-plus of our race. We all have a role and a stake in how we (and the grizzlies) make out.

Kindly Grandpa's bumper sticker resonates: People suck. But only when they're blind to destiny. The Anthropocene has arrived. What will we do with our species and our planet?

Peter M. Leschak, of Side Lake, Minn., is the author of "Ghosts of the Fireground" and other books.