Mr. Herzog uses the documentary not only to summon amazing Kinski stories but also to contemplate the actor's authentic (if erratic) genius.

Peter Bradshaw: If any film deserves to be called a work of authentic genius, it is this one.

His authentic genius expressed itself from his beginnings without hesitation, without wavering.

It testifies to the fact that authentic genius, even when trammeled by the necessities of a modern, mechanical mint, can transform our coinage into a work of art.

In the words of the filmmaker Sergei Parajanov, Peleshyan is "one of the few authentic geniuses in the world of cinema".

How often does an authentic genius come along-an Einstein, a Beethoven, a Jesus?

In matters having anything to do with movie-making he was an authentic genius, though totally unpublicized, usually unemployed, and practically unpaid.

I'm a genius, a blinkin', true-blue, authentic, f'nanchal genius.

On Purdy's latest book jackets I hail him as "an authentic American genius"; emphasis on the two adjectives.

There is no more difficult game than to try spotting an authentic and enduring genius during his lifetime.