Go back to Digital Texts Skepticism Skepticism, philosophic position holding that the possibility of knowledge is limited, because of either the limitations of the mind or the inaccessibility of its object. The term is used more loosely to denote any questioning attitude. The earliest skeptics included the Greek Sophists (5th cent. B.C.) and Protagoras. David Hume is famous for his theoretical skepticism, but more closely linked to skepticism was the agnosticism of Kant, who demonstrated that certain problems are insoluble by reason. Descartes used skepticism as a methodology. The scientific method, which demands that all assumptions be questioned, is skeptical to a degree, although the of scientists assumes that material effect is impossible without material cause. From the Concise Columbia Encyclopedia. Copyright © 1991 by Columbia University Press.