The word “skepticism” comes from the ancient Greek skepsis, meaning “inquiry.” Skepticism is, therefore, not a cynical rejection of new ideas, as the popular stereotype goes, but rather an attitude of both open mind and critical sense.
The ancient skeptics simply doubted that human beings can achieve certain knowledge, and preferred to be agnostic about a number of notions which they felt we just did not grasp securely.
That philosophical tradition eventually informed the beginnings of science in the 17th and 18th centuries, and it is best captured by David Hume’s advice that wise persons proportion their beliefs to the evidence. Or, as Carl Sagan put it much later, extraordinary claims require extraordinary evidence.
The modern skeptical movement is a grassroots phenomenon that aims at helping the public navigate the complex borderlands between sense and nonsense, science and pseudoscience.
Skepticism does so by way of investigation of alleged extraordinary phenomena, mindful cultivation of critical thinking, and an honest attitude toward intellectual inquiry.
The Burden of Skepticism
Following is an excerpt from the Skeptical Inquirer archives (Vol. 12 Issue No.1) where Carl Sagan describes skepticism in his own words.
What Is Skepticism?
It’s nothing very esoteric. We encounter it every day. When we buy a used car, if we are the least bit wise we will exert some residual skeptical powers—whatever our education has left to us. You could say, “Here’s an honest-looking fellow. I’ll just take whatever he offers me.”
Or you might say, “Well, I’ve heard that occasionally there are small deceptions involved in the sale of a used car, perhaps inadvertent on the part of the salesperson,” and then you do something. You kick the tires, you open the doors, you look under the hood. (You might go through the motions even if you don’t know what is supposed to be under the hood, or you might bring a mechanically inclined friend.)
You know that some skepticism is required, and you understand why. It’s upsetting that you might have to disagree with the used-car salesman or ask him questions that he is reluctant to answer. There is at least a small degree of interpersonal confrontation involved in the purchase of a used car and nobody claims it is especially pleasant. But there is a good reason for it—because if you don’t exercise some minimal skepticism, if you have an absolutely untrammeled credulity, there is probably some price you will have to pay later. Then you’ll wish you had made a small investment of skepticism early. Now this is not something that you have to go through four years of graduate school to understand.
Everybody understands this. The trouble is, a used car is one thing but television commercials or pronouncements by presidents and party leaders are another. We are skeptical in some areas but unfortunately not in others.
Skeptics and Science Deniers
Public discussion of scientific topics such as global warming is confused by misuse of the term “skeptic.” A Nov. 10, 2014, New York Times article incorrectly referred to Sen. James Inhofe as “a prominent skeptic of climate change.” Two days later Scott Horsley of NPR’s Morning Edition called him “one of the leading climate change deniers in Congress.” These are not equivalent statements.
There is a concern that “skeptic” and “denier” have been conflated. Proper skepticism promotes scientific inquiry, critical investigation, and the use of reason in examining controversial and extraordinary claims.
It is foundational to the scientific method. Denial, on the other hand, is the a priori rejection of ideas without objective consideration.
As scientific skeptics, we are well aware of political efforts to undermine climate science by those who deny reality but do not engage in scientific research or consider evidence that their deeply held opinions are wrong.
The most appropriate word to describe the behavior of those individuals is “denial.” Not all individuals who call themselves climate change skeptics are deniers.
Skeptics are those who have devoted much of their careers to practicing and promoting scientific skepticism.