is (A) Philosophical skepticism - a philosophical position
in which people chooose to critically examine whether the knowledge and perceptions that they have are actually true, and whether or not on can ever be said to have true knowledge; or (B) Scientific skepticism - a scientific, or practical, position
in which one does not accept the veracity of claims until solid evidence is produced in accordance with the scientific method
Scientific skepticism is related to, but not identical to, philosophical skepticism. Many scientists and doctors who are skeptical of claims of the paranormal are nonetheless not adherents of classical philosophical skepticism. When critics of controversial scientific or paranormal claims are said to be skeptical, this only refers to their taking a position of scientific skepticism.