The Preble's meadow jumping mouse is an endangered species.

Or not.

Global warming is a present danger and is largely caused by man's activities since the dawn of the Industrial Revolution.

Or not.

On Thursday, the U.S. Fish and Wildlife Service proposed removing the Preble's mouse from the endangered species list in Wyoming, but continuing such protection in Colorado.

State politicians liked the decision, while environmentalists denounced it.

Former Vice President Al Gore argues that carbon dioxide emissions are a threat to life on Earth as we know it.

In response, an ad campaign launched by the Competitive Enterprise Institute suggests all that extra carbon dioxide might be good: "We breathe it out, plants breathe it in," the message intoned. "They call it pollution, we can it life."

This is all done with a veneer of science - that data-gathering, hypothesis-testing, unbiased method of inquiry that intends to arrive at "truth," or at least, unvarnished fact.

But clearly, genuine objectivity is a theological concept beyond the powers of mere mortals.

Even so, we might, at least, hope for some honesty, and an admission that sometimes all the facts will never be, and indeed, can never be, known.

As a matter of public policy, we should decide whether we think the mouse's existence is threatened or whether it is not. If we think it is, we can then decide whether that matters much.

But splitting what already is a subspecies into Colorado and Wyoming subgroups of the subspecies based on statelines that are no more than invisible demarcations, then pretending we have addressed the underlying question about peril to the mouse, borders on the bizarre.

With respect to global warming, science can inform public policy but will never determine it.

Some objection can always be raised on one point or another, while ignoring a substantial body of evidence.

Juries can never fully understand a defendant's life experience, thought processes and motivation. But jurors still must make inferences, and draw conclusions, based on the evidence at hand.

In the case of global warming, we must decide what, if any, collective action is warranted, knowing full well that real actions will have real economic consequences.

Action would require sacrifices in how we live, work, travel and use energy. It would cause pain.

But the worst outcome is to believe, as a matter of democratic and scientific consensus, that a substantial threat to our own survival does exist, and yet do nothing about it.

That's neither science, nor good public policy.

It's just plain stupidity.