Two pretty remarkable things happened in the space of a month or so. In August, Nvidia revealed that its CEO's video keynote at the GPU Technology Conference in April was entirely manufactured. Go have a look – you won't be able to tell. It looks absolutely real. But it's not. Even Jensen Huang is a CGI model, not a real person composed into a digital scene. Also, in August came the revelation that a new documentary about Anthony Bourdain, the late celebrity chef, contains deep faked audio. In one clip, you can hear Bourdain's voice expressing thoughts he had written in a letter to a friend. He was never recorded speaking those words.

It's uncanny. So-called deepfakes are indistinguishable from the real thing. Even though there are attempts to detect deepfakes, they are constantly being outdated by new technologies and techniques. Seeing (and hearing) is not believing anymore.