"在别人眼里，数学对于数学家是很容易的。错了， 那是一场斗争，艰苦而孤独，不确定能得到成果，而且需要很长时间的奋斗。数学家是热爱斗争的人。 "

Back in 1999, the critic Bruce Benderson published a landmark essay, Sex and Isolation, in which he observed: “We are very much alone. Nothing leaves a mark. Today’s texts and images may look like real carvings – but in the end they are erasable, only a temporary blockage of all-invasive light. No matter how long the words and pictures stay on our screens, there will be no encrustation; all will be reversible.”

This aspect of digital existence is among the concerns of Sherry Turkle of the Massachusetts Institute of Technology, who has been writing about human-technology interactions for the past three decades. She has become increasingly wary of the capacity of online spaces to fulfil us in the ways we seem to want them to. According to Turkle, part of the problem with the internet is that it encourages self-invention. “At the screen,” she writes in Alone Together (2011), “you have a chance to write yourself into the person you want to be and to imagine others as you wish them to be, constructing them for your purposes. It’s a seductive but dangerous habit of mind.”

In 1942, the American painter Edward Hopper produced the signature image of urban loneliness. Nighthawks shows four people in a diner at night, cut off from the street outside by a curving glass window: a disquieting scene of disconnection and estrangement. In his art, Hopper was centrally concerned with how humans were handling the environment of the electric city: the way it crowded people together while enclosing them in increasingly small and exposing cells. His paintings establish an architecture of loneliness, reproducing the confining units of office blocks and studio apartments, in which unwitting exhibitionists reveal their private lives in cinematic stills, framed by panes of glass.