In the radiant blue chamber of the ZPrinter 850, a skull is born. An ink-jet arm moves across a bed of gypsum powder, depositing a layer of liquid that binds the powder together in the shape of a cranial cross-section.

The History of Art is filled with forgeries, but are there fakes in digital art fields made from creative cut-and-pastes, collaborative works and infinite works? We approached four people who, pondering the notion of fake, point to characteristics specific to digital art.

One of the epigraphs that punctuate Invented Knowledge is from Pascal: "It is natural for the mind to believe and for the will to love; so that, for want of true objects, they must attach themselves to false". Whether it is natural or not, it would seem that the false – the extravagant, the fantastical, the grandiose – can at times be so seductive that we suspend our critical faculties in its consideration. Ronald Fritze, a historian and dean at Athens State University in Alabama, is concerned about, and clearly fascinated by, the pseudo-histories and pseudo-sciences – the stories of Atlantis, pre-Ice Age civilizations, the Ten Lost Tribes of Israel, and cosmic catastrophes – which, as he argues, developed in the last quarter of the nineteenth century and are still with us. "The delivery system for pseudohistorians and pseudoscientists of all stripes", Fritze writes, "now encompasses a charlatan’s playground of film, television, radio, magazines, and the net." Fritze, a committed posit