Section III: the sceptic epistemology and objective knowledge
The main idea of sceptic epistemology is that knowledge defined as justified true belief is not objective knowledge because conclusion of a rational argument cannot be justified simply upon the basis of premises which are neither self-evident nor infallible experience. As observed by Harald Thorsrud (2009: 147) in Ancient Scepticism, “If the sceptic can systematically block all of our attempts at justification, we will be left in the troubling position of believing that we ought to do what we cannot”. In this section, the subject of inquiry is the sceptic position with regard to objective knowledge. In one sense, the study of scepticism might be said to define epistemology by showing that the idea of knowledge as justified true belief is untenable. In order to address the problem of objective knowledge from the sceptic viewpoint, I begin with a brief history of sceptic epistemology.
Scepticism: historical origin
Academic scepticism and Pyrrhonism are two branches of scepticism in ancient Greece which are opposed to the Stoics, who maintain that knowledge is possible. Academics believe that this inability can be recognized although the knowledge claims cannot be justified. Pyrrhonians, on the other hand, claim that even this inability is not recognizable. Most of what we know about Pyrrhonian scepticism is based on its presentation by Sextus Empiricus. Pyrrhonians delineate their scepticism by reasoning that the search for justification leads to suspension of judgment, arguing that the lack of any legitimate way to decide which side of the disagreement is correct results in suspension of judgment or the conclusion that nothing can be known (Hazlett 2014).
Similarly, Chi-Ming Lam (2007: 2) describes the sceptics’ major claim as follows:
... the problem is that we are unable to verify or justify our beliefs rationally. In fact, this problem had been widely discussed by sceptical philosophers ... For example, Pyrrho of Elis, regarded as the founder of the sceptical tradition, suggests suspending judgement in order to achieve tranquillity, since good grounds can be found not only for any belief but also against it.
According to Sextus (1994), there are at least three modes of suspension of judgement. The mode derived from infinite regress maintains that the argument itself that is brought forth as a source of belief for the matter proposed itself also needs such a source, which also needs a source, and so ad infinitum, so that there is no point from which to start to establish anything, resulting in suspension of judgement. Sextus also argues that the mode of hypothesis, in which the dogmatists, thrown back ad infinitum, begin with something which has not been established, but merely claimed as an assumption. The reciprocal mode occurs when what ought to confirm the object under study actually needs the object under examination to make it convincing. In this case, the inability to use either claim in order to establish the other leads to suspension of judgement about both claims.
Sceptics offer two major reasons for their critique of objective knowledge: firstly, that, likewise, neither the intellectualist nor the empiricist can prove the existence of infallible premises, whether in terms of self-evident principles or sense experiences, and secondly, that inductive inference is unable to transmit the truth of fallible premises to conclusion. Hence, even a dogmatist who can demonstrate undisputable premises may not argue that inductive inference enables justification of a universal knowledge claim on the basis of a limited number of empirical facts.