Sceptics were a group of ancient philosophers who formulated set of arguments to show either that no knowledge is possible (academic scepticism) or there is not sufficient or adequate evidence to tell if any knowledge is possible. When there is no sufficient or adequate evidence to tell if any knowledge is possible then the skeptics advocated the suspension of judgment on all questions concerning knowledge (Pyrrhonian skepticism). The skeptics maintained firmly that on each subject, two opinions can be expressed which exclude each other mutually namely affirmation and negation. It was held by the skeptics that even our knowledge of things is uncertain. Initially, Greek skepticism centered on the value of enquiry and questioning but Skepticism is now viewed as the denial that knowledge or even rational belief is possible. Academic skepticism was developed by philosophers Arcesilaus and Carneades into a series of arguments which were directed largely against the Stoic philosophers. A series of problems were submitted by Plato’s academics to show that what one thinks to know by senses may be unreliable and one cannot be sure about the reliability of one’s own reasoning. From a classical point of view, Skepticism is launched from the observation that the best methods in some area fall short of giving the contact with the truth. As an example it can be said that there is a wide chasm between appearance and reality. Academic skepticism dominated the philosophical outlook of Plato’s academy until the first century BC. The skeptics counseled Epoche or the suspension of belief. They also celebrated a way of life whose objective was Ataraxia or the tranquility which results from such suspension of belief. It must be noted that philosophical thoughts of three Skeptic philosophers Aenesidemus of Cnossos, Pyrrho of Elis and Sextus Empiricus throw tremendous light on skepticism. Aenesidemus was famous for having formulated ten tropes whereby inconsistent but equally defensible claims about matters of fact are established. Pyrrho is credited with the formulation of fundamental skeptical rhythms of Isosthenia – balancing of opposite opinions, Epoche-Suspension of belief, Aphasia – silence and Ataraxia- goal of tranquility. Lastly, the skepticism of Sextus Empiricus was confined to the Adela or theoretical world beyond experience in which the distinction between indicative signs and recollective signs is central.
