The Invention Of Lying is single-concept comedy, played out to ridiculous and often entertaining levels, but ultimately comes off a little flat as if from a script-reading rather than actual performances. That concept, that an alternate Earth (assumption here – the metaphysics of this closely-resembling Earth are never explained) is inhabited by humans who have never learned to lie. Ricky Gervais plays a man who one day in a pressure situation tells the world’s first lie. And the more he lies, the more he benefits from it because regular people perceive everything that comes out of their mouths is the truth.
If Ricky says his friend isn’t driving drunk, even though the police officer just administered a drunk driving test, then the driving test must be broken. If Ricky says his bank account has an extra few hundred bucks instead of being depleted, then the computer must be broken. This is a fine point, but this movie isn’t so much the invention of lying but the invention of being incorrect, because every normal (foil) person believes everything that anyone says. Because it is spoken, it is so. I speak, therefore what I say is a fact. (There is apparently no word for ‘truth’ just as there is no word for ‘lie’.)
We could examine whether this is also more a fact versus opinion exercise, or a mixture of all of these to suit the picture, but about halfway through the film we get to the whole point of the enterprise – using the invention of lying to invent religion. Because in a world without lying, there *is* no religion. That is, until Ricky makes up a story of a paradise beyond death to assuage his mother on her deathbed. The attendant overhear his merciful story and assume he knows all about this afterlife.