Full Idea
They collect someone's opinions together during the discussion, put them side by side, and show that they conflict with each other at the same time on the same subjects.... The person sees this, gets angry at themselves, and calmer towards others.
Gist of Idea
In discussion a person's opinions are shown to be in conflict, leading to calm self-criticism
Source
Plato (The Sophist [c.358 BCE], 230b)
Book Reference
Plato: 'Complete Works', ed/tr. Cooper,John M. [Hackett 1997], p.250
A Reaction
He goes on to say that the process is like a doctor purging a patient of internal harms. If anyone talks for long enough (even a good philosopher), their opinions will probably be seen to be in conflict. But which opinions do you abandon?