Skepticism

Skepticism, in epistemology, is the theory that certain knowledge is impossible. Skeptics believe we can't truly know anything for sure, because our senses and reasoning may deceive us. They doubt the certainty of our beliefs or claim that absolute certainty is unobtainable, prompting us to question what we think we understand. This doesn't mean skeptics disbelieve everything; rather, they simply refrain from absolute faith in knowledge.