Full Idea
The ancient Academic sceptics charged the Pyrrhonian sceptics with 'negative dogmatism' when they claimed that a certain kind of knowledge is impossible.
Clarification
'Dogmatism' is strong belief which is unjustified
Gist of Idea
Academics said that Pyrrhonians were guilty of 'negative dogmatism'
Source
report of Pyrrho (reports [c.325 BCE]) by Robert Fogelin - Walking the Tightrope of Reason Ch.4
Book Reference
Fogelin,Robert: 'Walking the Tightrope of Reason' [OUP 2004], p.114
A Reaction
It is this kind of point which should push us towards some sort of rationalism, because certain a priori 'dogmas' seem to be indispensable to get any sort of discussion off the ground. The only safe person is Cratylus (see Idea 578).
Related Idea
Idea 578 Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle]