Philosophy
Sextus Empiricus develops Pyrrhonian arguments for suspending judgment when opposing claims appear equally persuasive.
In this tradition, scepticism is presented as an ability rather than a set of doctrines: the knack of setting appearances and thoughts against one another on any question at all. What separates the sceptic from other thinkers is said to be an attitude toward problems, not the content of a position, since there is no position to defend.
For every argument the sceptic tries to find an opposing one of equal weight. When the two sides balance exactly, there is no rational ground for choosing either, and judgment is suspended. On this account the question shifts from whether knowledge is possible to whether forming a belief is rational at all.
For the sceptic, an argument is better than another only to the extent that it more effectively brings about suspended judgment. Arguments are used as tools to restore balance against a belief, not as proofs meant to establish a truth.
The sceptic's case against proof can cancel itself once it has done its work, the way a purgative clears the body and is then flushed out along with everything else. This is offered as the reply to the charge that arguing against all proof is self-refuting: the sceptic is not left holding the argument as a doctrine.
The sceptic is said to hold no beliefs on philosophical, scientific or theoretical matters, though interpreters disagree over whether this means no beliefs at all. One reading puts the difference in where beliefs come from: the dogmatist claims to reach them through rigorous inquiry, while the sceptic's views do not rest on such inquiry.
Saying that things look different to different observers invites a slide into relativism. One reading of the sceptic's response is that it recasts such cases as undecidable: when appearances conflict and nothing settles which one is right, judgment should be withheld rather than each appearance being declared true for someone.
The sceptic's claim is that tranquillity comes after suspending judgment, as a consequence rather than as a goal pursued directly. The text presents suspension of judgment as the only route to that calm, which arrives once one stops forcing a verdict on questions that cannot be settled.