Depending on what you've been conditioned to believe, you can come to the long conclusion consulting a supercomputer or the atmosphere.
It's still hot and it's still dry in the nation's drought-stricken farm belt.
It wasn't even noon today when the temperature at Sioux Falls in South Dakota was over 100.
Is this summer's terrible heat just temporary freakish weather, or is there a change in the atmosphere caused by our pollution?
The first signs of that greenhouse effect that scientists have warned us about.
That was back in the summer of 88 when an unusual heat wave seemed to foreshadow the arrival of the greenhouse effect.
But what are we going to conclude now? That the winter of 94 has been colder than usual.
What concerns me in a very general sense is not only that the politics or the policies can get ahead of the science,
but that the policies become, as it were, cast in concrete.
So that if the science changes, and science often does change, the policy accepted marches on.
What they've done is try to take scientific understanding and put it on the same level with political opinion.
After all, if scientific understanding is the same as political opinion, then everybody's opinion is equally valid.
There are no facts. And if there are no facts, there is no extra validity to acting on environmental problems,
than not acting.
That's why the stakes are so enormous.
The implication is that we will pay for the sins of industrialized society sooner or later.
But should we start imposing costly changes on our way of life to deal with a threat that has not yet totally revealed itself?
The suggestion is that if we don't, and the planet warms to the degree that some scientists predict, we will wish that we had.
Virtually everybody agrees that if we keep doing what we're doing right now for a long period of time, that bad things may happen.
But we're pretty vague about what those bad things are, and if or when they will happen.
Richard Lindzen, though, argues that the solution is possibly worse than the problem, and more likely to occur.
We would have to virtually, you know, the usual statement is cut emissions not to 1990 levels,
but to somewhere between 40 and 70 percent below 1990 levels.
And there's no one who's ever figured out how you could do that without virtually demolishing society as we know it.
There is some irony in the fact that Vice President Gore, one of the most scientifically literate men to sit in the White House in this century,
that he is resorting to political means to achieve what should ultimately be resolved on a purely scientific basis.
I'll have a closing thought on that in a moment.
Even when I know something is good for me, just getting started could be the hardest part.
It was that way when I first began working out. I still have to push myself to get started in the morning.
But I made a commitment to myself. And if it cost me time and energy, that's all right. I'm worth it.
I've made another commitment to myself, a college degree. I'm going to get my mind in shape, too.
The hardest part was just deciding to do it. The education counselor showed me that getting started was really not a problem at all.
He gave me advice on financial assistance, testing programs, and even choosing courses.
The studying takes time, and sometimes it's hard. But I'm going to go as far as I can, and education is going to help me get there.
The issues of global warming and ozone depletion are undeniably important.
The future of mankind may depend on how this generation deals with them.
But the issues have to be debated and settled on scientific grounds, not politics.
There is nothing new about major institutions seeking to influence science to their own ends.
The church did it. Ruling families have done it. The communists did it. And so have others in the name of anti-communism.
But it has always been a corrupting influence, and it always will be.
The measure of good science is neither the politics of the scientist nor the people with whom the scientist associates.
It is the immersion of hypotheses into the acid of truth.
That's the hard way to do it, but it's the only way that works.
That's our report for tonight. I'm Ted Koppel in Washington. For all of us here at ABC News, good night.
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