It was thought to be a rather ordinary Baroque painting, by an unknown disciple of Guido Reni, so its reserve price at a Paris auction house was €6,000. But the baroque depiction of Moses sold just over a year ago for a staggering €600,000.[1] Art dealer Fabrizio Moretti was so convinced of its worth, he outbid all the competition.[2] He had the painting restored, uncovering a striking luminesce beneath the ageing varnish and centuries of filth, and confirmed that it was by the Baroque master Giovanni Barbieri, known as “Guercino”—the squinter—because of a lazy eye that clearly didn’t compromise…