inarguable 

uncontestable, something no sane person would argue against
also, more commonly, inarguably

I am the best. It's inarguable.

inarguable by SR April 3, 2004

inarguably

hyperbole, usually added to strengthen a point which the speaker feels should be uncontestable but which is nevertheless in question

Bush inarguably lied about Saddam's connection to Al Qeada.

inarguably by sreed April 3, 2004