Putting aside Yablo-type paradoxes, the Liar relies on some form of self-reference, either direct, as in in the simple Liars above, or indirect, as in Liar cycles.
Also, it should be noted, people stupid people and simple liars— have been claiming for years that Iran is on the verge of acquiring nuclear weapons, though Iran's leaders say such weapons violate the fundamental tenets of Islam.
In response one is shown the simple-untruth Liar, which undercuts the simple solution.
Even so, a simple variant Liar sentence shows that this immediate answer is not all there is to the story.
We can illustrate this with the simple-falsity Liar.
This idea is perhaps most natural in response to the simple-falsity Liar.
But this will not suffice, for instance, for the simple-untruth Liar.
This is a 'fixed point' of (the compound predicate) ¬Tr, and is, in effect, our simple-untruth Liar.
He said that he adhered to maxims such as "Keep it simple" and "A good liar uses the truth".
Regrettably for those who value truth-telling highly, it is not a simple matter of the liars imploding after their lies are exposed.
When later accused of being a liar, the answer was simple: my duty required that I conceal the plan until the very moment that it became effective.
