A: all llamas are stripy
B: Anyone who thinks all llamas are stripy is clearly a buffoon.
A: The evidence clearly shows that calling people names is unacceptable .
B: It is clearly not true that calling people names is unacceptable .
A: You're wrong.
B: It is not evident that calling people names is unacceptable .
A: You're quite wrong, all llamas are stripy
B: It is quite obvious that it is not the case that all llamas are stripy
MoonShadow/FlameWar