Sophistic epistemology is, to put it simply, that there are no absolute Truths—but if there were absolute truths, we as humans wouldn't be able to comprehend or communicate them (Smith 41). They did, however, believe that there were socially constructed probable truths.
The Sophists viewed truth to be subjective. This means "they understood knowledge to be inherently flawed and imperfect, always changing given the situation, and open to interrogation and refutation." Since they viewed truth in this way, it makes sense that they would encourage the questioning of "traditional knowledge". (Lee 2017)
Rhetoric
The Sophists viewed rhetoric as very important. Since they believe that there are no absolute Truths but only probably truths, they used rhetoric to navigate the world by using rhetoric to create potential or probable truths. These potential truths they created "can be refined by pitting opposing positions against one another and examining the arguments thus brought forward" (Bizzel and Herberg 22). This process is called dissoi logoi. The Sophists believed every one creates their own version of reality that is shaped by rhetoric, and can only present this one unique reality. We must then decide what the best reality is by using rhetoric.
The Sophists valuedkairos. Kairos considers the appropriateness and timeliness of a moment or situation. Kairos was an important consideration in the use of rhetoric for the Sophists.
They believed rhetoric was a teachable art; many were teachers and speechmakers (Lee 2017). They also believed that philosophy and rhetoric went hand in hand, and therefore considered themselves to be both philosophers and rhetoricians (Lee 2017). The Sophists believed they could use rhetoric for the betterment of themselves, and wanted to develop arêtein their students through their teachings (Smith 41).
The Sophists weren't looked on very highly by other rhetoricians and few Sophist texts are still around today. This is partly because many texts were lost when the library in Alexandria was burnt to the ground (Lee 2017) and also "because of the scorn heaped on their work by those who came after, especially Plato" (Bizzel and Herzberg 23). By others, the Sophists seemed to use language to be manipulative and untruthful.