Rather than go into a single definition of what modern skepticism is, already done in great detail on this blog's Media Guide to Skepticism page by Sharon Hill, I’d like to discuss those aspects, those three faces, that to my understanding make it up.
What are those faces of skepticism? They are:
Skepticism is a set of values, both intellectual and ethical: Skepticism favors intellectual honesty, sincerity, integrity, and a high value on the truth of whatever matter we look into. It is to have little patience with those who deceive, save those ‘honest liars,’ professional conjurors who are forthright about the inherently deceptive nature of their trade. Those who knowingly defraud, harm, or manipulate others are fair game for skeptical scrutiny and critiquing. Skepticism acknowledges and respects the limits of human perception, understanding and reasoning. It tells us about and arms us against our biases. It tells us that “I don’t know,” is a better answer to a question than an answer that is not only demonstrably false, but isn’t even worthy of being wrong. If a skeptic is in error, or is knowingly dishonest, they can be and ought to be be corrected, or exposed, by others who are not. Whatever their personal inclinations, if they are not honest, other skeptics will be, and they will be found out.
Skepticism is a set of methods, a way of evaluating arguments and evidence to determine the likely factual status of claims. These are the methods of science, empiricism, and rational inquiry. Skepticism lets us know when someone’s trying to put us on, or putting others on, and that’s the first step to exposing them. Skepticism lets us distinguish sound claims from unsound and good argument from bad. It lets us know, when we are careful, when our prejudices are being pandered to, giving us the first line of defense against fraud and chicanery. These methods assume scientific literacy, scientific thinking, and an understanding of how we deceive ourselves and others through biases and motivated reasoning.
The values and methods of skepticism assume a particular approach to reality. It assumes that there are such things as facts and truth. It assumes the world is knowable and that it is possible to tell truth from falsehood. It assumes that the world is real, regardless of the nature of that reality, it exists, and that it must for anything at all to be meaningfully true, false, or even possible. It assumes that the methods of science, empiricism, and rational inquiry are valid, useful, and powerful ways of knowing reality. It assumes in its methods that solid, reliable and effective ways of knowing are preferable to those that not only lead to error, but are neither self-correcting nor concerned with the actual truth of a matter. While it doesn’t necessarily assume philosophical naturalism, it does assume naturalistic methods, and so eschews resorting to unobservable or unfalsifiable ‘explanations’ for phenomena. But it has no trouble investigating anything that is knowably real and open to objective inquiry.
These are the three faces and together they form the core of my understanding of skepticism as an endeavor, whatever the state of organized skepticism at any time.