It took most of mankind's existence to develop our most valuable tool for understanding the physical world and shaping it to meet our needs: the scientific method.
The key to its widespread use, beginning in the 17th century, was the growing freedom to pursue truth objectively, instead of submitting to the dogmas of church or state.
Today, however, we risk moving backward. Science is under attack by self-serving interest groups that reject objective inquiry because it frequently fails to produce politically desired results. A prime example is the failure of man-made global warming advocates to prove their case scientifically, but the attack covers many other issues as well.
One obvious abuse of the scientific process is the manner in which global-warming advocates have substituted consensus for verifiable proof. Many environmentalists insist that the issue is "settled" because large numbers of scientists agree with them.
However, that proves nothing. As the late science novelist Michael Crichton said in a 2003 speech: "Let's be clear: The work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science requires only one investigator who happens to be right, which means that he or she has results that are verifiable."
"The greatest scientists in history," Crichton observed, "are great precisely because they broke with the consensus."
A clear example of the pitfalls of using consensus to determine truth is the once universally held belief that ulcers were caused by stress — accepted by essentially every doctor, medical researcher, hospital, medical school, medical textbook, medical journal and pharmaceutical company in the world.
All of them were wrong. Two Australian scientists won the 2006 Nobel Prize for proving that up to 90 percent of peptic ulcers are caused instead by bacteria.
Closely related to consensus is the blind acceptance of "peer review" as the final word on a study's value. Peer review is most useful when a scientist proposes a new hypothesis and seeks the advice of other experts about how to proceed. Otherwise, it is simply the opinions of other scientists about the acceptability of a proposed hypothesis, not its validity. Even if all other scientists agree with a hypothesis, that does not equal proof.
Peer review's shortcomings were once exposed by the editors of the British Medical Journal, who deliberately inserted eight errors into an unpublished paper. The 221 scientists who reviewed the paper found an average of just two errors. Nobody found more than five and 16 percent of the peer reviewers found none.
Elsewhere, South Korean scientist Hwang Woo Suk was able to publish articles in top peer-reviewed journals about his success in cloning human embryos — until a government panel proved his claims to be fraudulent.
Computer modeling also is used as a substitute for empirical proof. Even the best models are merely the researcher's interpretation of the physical world, so they cannot predict the future with certainty. The most glaring example of this was the 2008 stock market collapse, largely caused by overreliance on sophisticated computer models, created by experts.
Perhaps the most aggressive attacks against science are attempts to inject value-driven methods into traditional science.
"Post-normal science," for example, is a decision-making tool some would use in situations when "facts are uncertain, values are in dispute, stakes are high, and decisions are urgent." That is not the realm of science, but of politics. After all, who's to decide whether decisions are so "urgent" they must be made even when "facts are uncertain?"
Another suspect tactic is invoking the "precautionary principle." This principle holds that when an activity is thought to threaten human health or the environment, "precautionary measures should be taken" even in the absence of proof that the activity in question is responsible. As the pressure to adopt these and other pseudo-scientific methods increases, science is perverted.
The development of the modern scientific method during the Enlightenment resulted in enormous progress for mankind. Deviating from strict adherence to the time-tested scientific process will result in an equally dramatic upheaval — only this time, it will be a decline.
Genuine science must be defended. The alternative is a new kind of Dark Ages.
John Droz Jr., a retired physicist and an environmental activist living in North Carolina, is a senior fellow at the American Tradition Institute in Washington, D.C. Jay Schalin is director of state policy analysis at the Pope Center for Higher Education Policy (popecenter.org) in Raleigh, N.C.