Writing in the Washington Post, Harvard astronomer Howard Smith forcefully blunts Stephen Hawking’s assertion that “The human race is just a chemical scum on a moderate-sized planet.” Of course, it’s not only Dr. Hawking who says as much — denying human exceptionalism is close to universal orthodoxy among the socio-academic demographic he occupies. Carl Sagan put the same view a little more mildly: “We find that we live on an insignificant planet of a humdrum star.”

Smith points out, however, that science considered objectively is much closer to the exceptionalist conclusion. In truth, humanity is something momentous in the cosmos. Weighing these assertions by Hawking and Sagan, Smith writes:

An objective look…at just two of the most dramatic discoveries of astronomy — big bang cosmology and planets around other stars (exoplanets) — suggests the opposite. We seem to be cosmically special, perhaps even unique — at least as far as we are likely to know for eons.

He cites the anthropic principle and the “misanthropic principle.”

The first result — the anthropic principle — has been accepted by physicists for 43 years. The universe, far from being a collection of random accidents, appears to be stupendously perfect and fine-tuned for life. The strengths of the four forces that operate in the universe — gravity, electromagnetism, and the strong and weak nuclear interactions (the latter two dominate only at the level of atoms) — for example, have values critically suited for life, and were they even a few percent different, we would not be here. The most extreme example is the big bang creation: Even an infinitesimal change to its explosive expansion value would preclude life. The frequent response from physicists offers a speculative solution: an infinite number of universes — we are just living in the one with the right value. But modern philosophers such as Thomas Nagel and pioneering quantum physicists such as John Wheeler have argued instead that intelligent beings must somehow be the directed goal of such a curiously fine-tuned cosmos.

As for the second point, about exoplanets:

The discovery of exoplanets was dramatic but not unexpected: Since the Greeks, we have imagined planets were common. Textbooks even taught that our solar system was typical. But the exotic diversity of exoplanets came as a surprise. Many have highly elliptical orbits around unstable stars, making evolution over billions of years difficult if not impossible; other systems contain giant planets that may have drifted inward, disrupting orbits; and there are many other unanticipated properties. These unexpected discoveries are helping scientists unravel Earth’s complex history.

The bottom line for extraterrestrial intelligence is that it is probably rarer than previously imagined, a conclusion called the misanthropic principle. For all intents and purposes, we could be alone in our cosmic neighborhood, and if we expand the volume of our search we will have to wait even longer to find out. Life might be common in the very distant universe — or it might not be — and we are unlikely to know. We are probably rare — and it seems likely we will be alone for eons. This is the second piece of new evidence that we are not ordinary.

Asking colleagues to put aside “beliefs” in favor of objective scientific “observations” like these, Dr. Smith concludes on a hortatory note:

It seems we might even serve some cosmic role. So this season let us be grateful for the amazing gifts of life and awareness, and acknowledge the compelling evidence to date that humanity and our home planet, Earth, are rare and cosmically precious. And may we act accordingly.

Atheists aren’t having any of it. At Why Evolution Is True, biologist Jerry Coyne hits back, complaining that Smith doesn’t confess right up front that he is in fact, as Smith himself has written elsewhere, an observant Jew. Coyne frets that Smith is a “religious Jew who spends his time reconciling science with the mystical tenets of the Kaballah.” Actually from his bio it appears that Smith spends his time working as a “lecturer in the Harvard University Department of Astronomy and a senior astrophysicist at the Harvard-Smithsonian Center for Astrophysics.” Coyne, a retired academic who spends a fair amount of his own time posting pictures and videos of cute cats, rants:

What galls me about Smith’s article is that, in light of his known views, he’s trying to hide his argument for God, all the while leading the reader to think that there must be a god running our Universe. His piece is deliberately misleading — indeed, duplicitous.

If Smith thought that scientific evidence confirms his religious views in all their details, he could have written that, though it would have provided an even easier excuse to dismiss him.

Or perhaps, more reasonably, he agrees with ID advocates that science takes you so far and no farther, leading only to the minimal conclusion that life bears evidence of design. From a description of a 2006 book Smith wrote, linked by Coyne, it’s unclear. Smith does, however, say this: “Scientists have been admirably honest about admitting ignorance, and, it seems to me, offer a lesson in humility to theologians: we do not know it all, regardless of our Scriptures…or our egos.”

Photo: Spiral galaxy NGC 3274, by ESA/Hubble & NASA, D. Calzetti.