To read into the mind of another person has for a long time been a fantasy—and sometimes a vague possibility. In science fiction, there are stories of aliens who are able to decipher the thoughts of other beings using some type of device. When I was a boy, I remember reading a cartoon of Bibi Fricotin, in which Bibi, a young boy like me, found some glasses that allowed him to read other people’s thoughts. For a time, I was afraid when I came across adults wearing glasses. With such devices, privacy and childish innocence would be in jeopardy, but fortunately, this was only a remote possibility. The idea would be worrying for lay people, ethicists and lawyers, but it is only a fantasy. Recently, with the development of brain imaging, the reality of this old fantasy seems less remote and even possible.